1000 or 1,000 (one thousand) is the natural number following 999 and preceding 1001.
In mathematics
- The decimal representation for one thousand is
- 1,000—a one followed by three zeros, in the general notation ;
- 1 × 10^{3}—in engineering notation, which for this number coincides with :
- 1 × 10^{3} exactly—in scientific normalized exponential notation ;
- 1 E+3 exactly—in scientific E notation.
- The SI prefix for a thousand is kilo-, officially abbreviated as k—for instance prefixed to "metre" or its abbreviation m, kilometre or km signifies a thousand metres, as such, technically oriented people occasionally represent the number in a non-standard notation by replacing the last three zeros of the general numeral with "k", for instance, 30k for 30,000.
- By the SI writing style, a comma or a space can be used to as a Thousands separator, i.e., to separate the digits of a number every power of 1000.
- The sum of Euler's totient function over the first 57 integers is 1000.
- mentions that 1000 is the smallest number that generates three primes in the fastest way possible by concatenation of decremented numbers (1000999, 1000999998997, and 1000999998997996995994993 are prime). The criterion excludes counting the number itself.
- 1000 is a Harshad number in base 10.
In time
- A millennium is 1000 years. The year 1000 was the last year of the 1st millennium.
In popular culture
- A grand is a slang term for one thousand units of a given currency. Several grand can be shortened to Gs.
- Especially in the United States, the gambling community often refers to denominations of $1000 as dimes
- A picture is worth a thousand words
- According to an ancient Japanese legend, anyone who folds a thousand origami cranes will be granted a wish by a crane.
Miscellaneous
- Thousand Oaks, California
- Metal Mining SIC Code
- Thousand Island dressing
Music
- Thousand Foot Krutch, an alternative rock band
- I Feel It/Thousand, a 1993 techno single by Moby
- A Thousand Suns, a 2010 album by Linkin Park
- A Thousand Years, a 2011 song by Christina Perri
- A Thousand Miles, a 2002 song by Vanessa Carlton
- A Thousand Answers, a 2012 song by The Hives
Selected numbers in the thousands (1001–1999)
1001–1249
- 1001 – sphenic number (7 × 11 × 13), pentagonal number, pentatope number
- 1002 – sphenic number, Mertens function zero, abundant number
- 1005 – Mertens function zero
- 1008 – divisible by the number of primes below it
- 1009 – first prime above 1000
- 1010 – Mertens function zero
- 1013 – Sophie Germain prime, centered square number, Mertens function zero
- 1014 – Mertens function zero
- 1015 – square pyramidal number
- 1016 – member of the Mian–Chowla sequence
- 1017 – Brick Squad
- 1018 – Mertens function zero
- 1019 – Sophie Germain prime, safe prime
- 1020 – polydivisible number
- 1023 – the highest number one can count to on one's fingers using binary; also the magic number used in Global Positioning System signals
- 1024 – , the number of bytes in a kilobyte (in 1999, the IEC coined kibibyte to use for 1024 with kilobyte being 1000, but this convention has not been widely adopted)
- 1025 - often featured in the webcomic Homestuck.
- 1027 – sum of the squares of the first eight primes; can be written from base 2 to base 18 using only the digits 0 to 9.
- 1028 – sum of totient function for first 58 integers; can be written from base 2 to base 18 using only the digits 0 to 9.
- 1029 – can be written from base 2 to base 18 using only the digits 0 to 9.
- 1031 – Sophie Germain prime
- 1033 – locale ID of English (United States) in (some version of) Windows..
- 1035 – triangular number, hexagonal number
- 1049 – Sophie Germain prime, highly cototient number
- 1051 – centered pentagonal number
- 1056 – pronic number
- 1060 – sum of the first 25 primes
- 1071 – heptagonal number
- 1072 – centered heptagonal number
- 1079 – every positive integer is the sum of at most 1079 tenth powers.
- 1080 – pentagonal number
- 1081 – triangular number, member of Padovan sequence
- 1086 – Smith number, sum of totient function for first 59 integers
- 1087 – Chen prime, cousin prime, lucky prime, Kynea number
- 1089 – , nonagonal number, centered octagonal number
- 1091 – cousin prime and twin prime
- 1092 – divisible by the number of primes below it
- 1093 – the smallest Wieferich prime (the only other known Wieferich prime is 3511), twin prime and star number
- 1102 – sum of totient function for first 60 integers
- 1103 – Sophie Germain prime, balanced prime
- 1104 – Keith number
- 1105 – Carmichael number, magic constant of n × n normal magic square and n-queens problem for n = 13, decagonal number, centered square number, 1105 = 33^{2} + 4^{2} = 32^{2} + 9^{2} = 31^{2} + 12^{2} = 23^{2} + 24^{2}
- 1111 - often featured in the webcomic Homestuck, although more commonly used is 111111, multiples of 11, or 2x3.
- 1116 – divisible by the number of primes below it
- 1122 – pronic number, divisible by the number of primes below it
- 1123 – balanced prime
- 1124 – Leyland number
- 1128 – triangular number, hexagonal number, divisible by the number of primes below it
- 1134 - divisible by the number of primes below it
- 1138 – recurring number in the works of George Lucas and his companies, beginning with his first feature film – THX 1138; particularly, a special code for Easter eggs on Star Wars DVDs.
- 1140 – tetrahedral number
- 1152 – highly totient number
- 1153 – Proth prime
- 1156 – , octahedral number, centered pentagonal number
- 1159 – member of the Mian–Chowla sequence
- 1161 – sum of the first 26 primes
- 1162 – pentagonal number, sum of totient function for first 61 integers
- 1169 – highly cototient number
- 1170 – highest possible score in a National Academic Quiz Tournaments (NAQT) match
- 1176 – triangular number
- 1177 – heptagonal number
- 1184 – amicable number with 1210
- 1187 – safe prime, Stern prime, balanced prime
- 1190 – pronic number
- 1192 – sum of totient function for first 62 integers
- 1198 – centered heptagonal number
- 1200 – the number of households the Nielsen ratings sample
- 1201 – centered square number
- 1210 – amicable number with 1184
- 1216 – nonagonal number
- 1217 – Proth prime
- 1219 – Mertens function zero
- 1220 – Mertens function zero
- 1223 – Sophie Germain prime, balanced prime
- 1225 – , triangular number, square triangular number, hexagonal number, centered octagonal number
- 1228 – sum of totient function for first 63 integers
- 1229 – Sophie Germain prime
- 1233 –
- 1240 – square pyramidal number
- 1241 – centered cube number
- 1242 – decagonal number
- 1247 – pentagonal number
- 1249 – emirp, trimorphic number
1250–1499
- 1255 – Mertens function zero
- 1256 – Mertens function zero
- 1258 – Mertens function zero
- 1259 – highly cototient number
- 1260 – highly composite number, pronic number, the smallest vampire number, sum of totient function for first 64 integers, this number appears twice in the Book of Revelation
- 1261 – star number, Mertens function zero
- 1264 – sum of the first 27 primes
- 1266 – centered pentagonal number, Mertens function zero
- 1270 – Mertens function zero
- 1275 – triangular number, sum of the first 50 natural numbers
- 1279 – Mertens function zero
- 1280 – Mertens function zero
- 1282 – Mertens function zero
- 1283 – safe prime
- 1285 – Mertens function zero
- 1288 – heptagonal number
- 1289 – Sophie Germain prime, Mertens function zero
- 1291 – Mertens function zero
- 1292 – Mertens function zero
- 1296 – 6^{4}, 36^{2}, sum of the cubes of the first eight positive integers, the number of rectangles on a normal 8 × 8 chessboard
- 1297 – Mertens function zero
- 1299 – Mertens function zero
- 1300 – Sum of the first 4 fifth powers, mertens function zero, largest possible win margin in an NAQT match
- 1301 – centered square number
- 1302 – Mertens function zero
- 1306 – Mertens function zero
- 1307 – safe prime
- 1308 – sum of totient function for first 65 integers
- 1309 – the first sphenic number followed by two consecutive such number
- 1312 – member of the Mian–Chowla sequence
- 1318 – Mertens function zero
- 1319 – safe prime
- 1325 – Markov number
- 1326 – triangular number, hexagonal number, Mertens function zero
- 1327 – first prime followed by 32 consecutive composite numbers
- 1328 – sum of totient function for first 66 integers
- 1329 – Mertens function zero
- 1330 – tetrahedral number, forms a Ruth–Aaron pair with 1331 under second definition
- 1331 – 11^{3}, centered heptagonal number, forms a Ruth–Aaron pair with 1330 under second definition. This is the only cube of the form x^{2}+x-1, for x=36.
- 1332 – pronic number
- 1335 – pentagonal number, Mertens function zero
- 1336 – Mertens function zero
- 1337 – Used in the novel form of spelling called leet
- 1338 – Mertens function zero
- 1342 – Mertens function zero
- 1350 – nonagonal number
- 1365 – pentatope number
- 1367 – safe prime, balanced prime
- 1369 – 37^{2}, centered octagonal number
- 1371 – sum of the first 28 primes
- 1378 – triangular number
- 1379 – magic constant of n × n normal magic square and n-queens problem for n = 14.
- 1381 – centered pentagonal number
- 1387 – 5th Fermat pseudoprime of base 2, 22nd centered hexagonal number and the 19th decagonal number, second Super-Poulet number.
- 1394 – sum of totient function for first 67 integers
- 1395 – vampire number, member of the Mian–Chowla sequence
- 1404 – heptagonal number
- 1405 – , , centered square number
- 1406 – pronic number, semi-meandric number
- 1409 – Sophie Germain prime, smallest number whose eighth power is the sum of 8 eighth powers, Proth prime
- 1419 – Zeisel number
- 1425 – self-descriptive number in base 5
- 1426 – sum of totient function for first 68 integers
- 1426 – pentagonal number
- 1430 – Catalan number
- 1431 – triangular number, hexagonal number
- 1432 – member of Padovan sequence
- 1433 - Typical port used for remote connections to Microsoft SQL Server databases
- 1435 – vampire number; the standard railway gauge in millimetres, equivalent to 4' 8½"
- 1439 – Sophie Germain prime, safe prime
- 1440 – a highly totient number and a 481-gonal number. Also, the number of minutes in one day, the blocksize of a standard 3.5" floppy disk, and the horizontal resolution of WXGA(II) computer displays
- 1441 – star number
- 1444 – , smallest pandigital number in Roman numerals
- 1451 – Sophie Germain prime
- 1469 – octahedral number, highly cototient number
- 1470 – pentagonal pyramidal number, sum of totient function for first 69 integers
- 1471 – centered heptagonal number
- 1480 – sum of the first 29 primes
- 1481 – Sophie Germain prime
- 1482 – pronic number
- 1485 – triangular number
- 1487 – safe prime
- 1490 – tetranacci number
- 1491 – nonagonal number, Mertens function zero
- 1492 – Mertens function zero
- 1493 – Stern prime
- 1494 – sum of totient function for first 70 integers
- 1496 – square pyramidal number
- 1499 – Sophie Germain prime
1500–1749
- 1501 – centered pentagonal number
- 1511 – Sophie Germain prime, balanced prime
- 1513 – centered square number
- 1518 – Mertens function zero
- 1519 – Mertens function zero
- 1520 – pentagonal number, Mertens function zero, forms a Ruth–Aaron pair with 1521 under second definition
- 1521 – , Mertens function zero, centered octagonal number, forms a Ruth–Aaron pair with 1520 under second definition
- 1523 – Mertens function zero, safe prime, member of the Mian–Chowla sequence
- 1524 – Mertens function zero
- 1525 – heptagonal number, Mertens function zero
- 1527 – Mertens function zero
- 1528 – Mertens function zero
- 1530 – vampire number
- 1531 – Mertens function zero
- 1532 – Mertens function zero
- 1535 – Thabit number
- 1537 – Keith number, Mertens function zero
- 1540 – triangular number, hexagonal number, decagonal number, tetrahedral number
- 1543 – Mertens function zero
- 1544 – Mertens function zero
- 1546 – Mertens function zero
- 1556 – sum of the squares of the first nine primes
- 1559 – Sophie Germain prime
- 1560 – pronic number
- 1564 – sum of totient function for first 71 integers
- 1572 – member of the Mian–Chowla sequence
- 1575 – odd abundant number
- 1583 – Sophie Germain prime
- 1588 – sum of totient function for first 72 integers
- 1593 – sum of the first 30 primes
- 1596 – triangular number
- 1597 – Fibonacci number, Markov number, Prime number, emirp
- 1600 – , street number on Pennsylvania Avenue of the White House, Meters; Common High School Track Event, perfect score on SAT
- 1601 – Sophie Germain prime, Proth prime, the novel 1601 (Mark Twain)
- 1617 – pentagonal number
- 1618 – centered heptagonal number
- 1619 – safe prime
- 1625 – centered square number
- 1626 – centered pentagonal number
- 1633 – star number
- 1638 – harmonic divisor number
- 1639 – nonagonal number
- 1640 – pronic number
- 1649 – highly cototient number, Leyland number
- 1651 – heptagonal number
- 1653 – triangular number, hexagonal number
- 1657 – cuban prime
- 1660 – sum of totient function for first 73 integers
- 1666 – largest efficient pandigital number in Roman numerals (each symbol occurs exactly once)
- 1679 – highly cototient number, semiprime (23 × 73, see also Arecibo message)
- 1680 – highly composite number
- 1681 – , smallest number yielded by the formula that is not a prime; centered octagonal number
- 1682 – member of a Ruth–Aaron pair (first definition)
- 1683 – member of a Ruth–Aaron pair (first definition)
- 1695 – magic constant of n × n normal magic square and n-queens problem for n = 15.
- 1696 – sum of totient function for first 74 integers
- 1701 – decagonal number, hull number of the U.S.S. Enterprise on Star Trek
- 1705 – tribonacci number
- 1709 – first of a sequence of eight primes formed by adding 57 in the middle. 1709, 175709, 17575709, 1757575709, 175757575709, 17575757575709, 1757575757575709 and 175757575757575709 are all prime, but 17575757575757575709 = 232433 × 75616446785773
- 1711 – triangular number
- 1717 – pentagonal number
- 1720 – sum of the first 31 primes
- 1722 – Giuga number, pronic number
- 1728 – the quantity expressed as 1000 in duodecimal, that is, the cube of twelve (called a great gross), and so, the number of cubic inches in a cubic foot
- 1729 – taxicab number, Carmichael number, Zeisel number, centered cube number, Hardy–Ramanujan number. In the decimal expansion of e the first time all 10 digits appear in sequence starts at the 1729th decimal place. In 1979 the rock musical Hair closed on Broadway in New York City after 1729 performances.
- 1733 – Sophie Germain prime
- 1736 – sum of totient function for first 75 integers
- 1741 – centered square number
- 1747 – balanced prime
1750–1999
- 1753 – balanced prime
- 1756 – centered pentagonal number
- 1764 –
- 1770 – triangular number, hexagonal number, Town of Seventeen Seventy in Australia
- 1771 – tetrahedral number
- 1772 – centered heptagonal number, sum of totient function for first 76 integers
- 1782 – heptagonal number
- 1785 – square pyramidal number
- 1791 – largest natural number that cannot be expressed as a sum of at most four hexagonal numbers.
- 1794 – nonagonal number
- 1800 – pentagonal pyramidal number, also, in da Ponte's Don Giovanni, the number of women Don Giovanni had slept with so far when confronted by Donna Elvira, according to Leporello's tally
- 1801 – cuban prime
- 1806 – pronic number, product of first four terms of Sylvester's sequence, primary pseudoperfect number
- 1807 – fifth term of Sylvester's sequence
- 1811 – Sophie Germain prime
- 1820 – pentagonal number, pentatope number
- 1821 – member of the Mian–Chowla sequence
- 1823 – safe prime
- 1827 – vampire number
- 1828 – meandric number, open meandric number
- 1830 – triangular number
- 1832 – sum of totient function for first 77 integers
- 1834 – octahedral number, sum of the cubes of the first five primes
- 1836 – factor by which a proton is more massive than an electron
- 1837 – star number
- 1841 – Mertens function zero
- 1843 – Mertens function zero
- 1844 – Mertens function zero
- 1845 – Mertens function zero
- 1849 – , centered octagonal number
- 1851 – sum of the first 32 primes
- 1853 – Mertens function zero
- 1854 – Mertens function zero
- 1856 – sum of totient function for first 78 integers
- 1857 – Mertens function zero
- 1861 – centered square number, Mertens function zero
- 1862 – Mertens function zero, forms a Ruth–Aaron pair with 1863 under second definition
- 1863 – Mertens function zero, forms a Ruth–Aaron pair with 1862 under second definition
- 1864 – Mertens function zero
- 1866 – Mertens function zero
- 1870 – decagonal number
- 1885 – Zeisel number
- 1889 – Sophie Germain prime, highly cototient number
- 1891 – triangular number, hexagonal number, centered pentagonal number
- 1892 – pronic number
- 1896 – member of the Mian–Chowla sequence
- 1897 – member of Padovan sequence
- 1900 – 1900 (film) or Novecento, 1977 movie
- 1901 – Sophie Germain prime
- 1907 – safe prime, balanced prime
- 1909 – hyperperfect number
- 1918 – heptagonal number
- 1926 – pentagonal number
- 1929 – Mertens function zero
- 1931 – Sophie Germain prime
- 1933 – centered heptagonal number, prime number
- 1934 – sum of totient function for first 79 integers
- 1936 –
- 1938 – Mertens function zero
- 1951 – cuban prime, prime followed by a prime gap of 22.
- 1953 – triangular number
- 1956 – nonagonal number
- 1966 – sum of totient function for first 80 integers
- 1973 – Sophie Germain prime
- 1979 – prime number
- 1980 – pronic number
- 1984 – 11111000000 in binary, see also: 1984 (disambiguation)
- 1985 – centered square number
- 1988 – sum of the first 33 primes