2000 (number).html

2000 (two thousand) is the natural number following 1999 and preceding 2001.

List of numbers — Integers ← 1k 2k 3k 4k 5k 6k 7k 8k 9k →
Cardinal	2000 two thousand
Ordinal	2000th two thousandth
Factorization	$2000 = 2^4 \cdot 5^3$
Roman numeral	MM
Roman numeral (Unicode)	MM, mm
Binary	11111010000
Octal	3720
Duodecimal	11A8
Hexadecimal	7D0

Look up two thousand in
Wiktionary, the free dictionary.

See also: millennium, year 2000 AD, Y2K, 2000 (disambiguation).

Two thousand is the highest number expressible using only two unmodified characters in roman numerals (MM).

Two thousand is also:

In the name of the products Lever 2000 and Grecian 2000, Windows 2000
In Star Trek, the registry number of the USS Excelsior, NX-2000 in Star Trek III: The Search for Spock, and NCC-2000 commanded by Hikaru Sulu in Star Trek VI: The Undiscovered Country.
The postal code for Antwerp (Belgium) and Sydney (Australia)

Selected numbers in the range 2001-2999

2001 - sphenic number
2003 - Sophie Germain prime
2007 - Last year (Gregorian Calendar)
2008 - Current year (Gregorian Calendar)
2009 - Next year (Gregorian Calendar)
2015 - Lucas-Carmichael number
2016 - triangular number
2017 - Mertens function zero
2020 - sum of the totient function for the first 81 integers
2024 - tetrahedral number
2025 - $452$ , sum of the cubes of the first nine integers, centered octagonal number
2027 - safe prime
2029 - member of the Mian-Chowla sequence
2030 - $212 + 22 2 + 23 2 + 24 2$ , $252 + 26 2 + 27 2$
2031 - centered pentagonal number
2039 - Sophie Germain prime, safe prime
2047 - super-Poulet number, Woodall number, decagonal number
2048 - power of two
2056 - magic constant of n×n normal magic square and n-Queens Problem for n = 16.
2060 - sum of the totient function for the first 82 integers
2063 - Sophie Germain prime, safe prime
2069 - Sophie Germain prime
2070 - pronic number
2080 - triangular number
2093 - Mertens function zero
2095 - Mertens function zero
2096 - Mertens function zero
2097 - Mertens function zero
2099 - Mertens function zero, safe prime, highly cototient number
2100 - Mertens function zero
2101 - centered heptagonal number
2107 - member of a Ruth-Aaron pair with 2108 (first definition)
2108 - member of a Ruth-Aaron pair with 2107 (first definition)
2109 - square pyramidal number
2112 - The break-through album of the band Rush
2113 - Mertens function zero, Proth prime
2116 - $462$
2117 - Mertens function zero
2119 - Mertens function zero
2120 - Mertens function zero
2122 - Mertens function zero
2125 - nonagonal number
2127 - sum of the first 34 primes
2129 - Sophie Germain prime
2135 - Mertens function zero
2136 - Mertens function zero
2138 - Mertens function zero
2141 - Sophie Germain prime
2142 - sum of the totient function for the first 83 integers
2145 - triangular number
2162 - pronic number
2166 - sum of the totient function for the first 84 integers
2169 - Leyland number
2171 - Mertens function zero
2172 - Mertens function zero
2175 - smallest number requiring 143 seventh powers for Waring representation
2176 - pentagonal pyramidal number, centered pentagonal number
2179 - Wedderburn-Etherington number
2187 - $37$ , vampire number, perfect totient number
2188 - Motzkin number
2197 - $133$
2199 - perfect totient number
2205 - odd abundant number
2207 - safe prime, Lucas prime
2208 - Keith number
2209 - $472$ , centered octagonal number
2211 - triangular number
2223 - Kaprekar number
2230 - sum of the totient function for the first 85 integers
2232 - decagonal number
2254 - member of the Mian-Chowla sequence
2255 - octahedral number
2256 - pronic number
2269 - cuban prime
2272 - sum of the totient function for the first 86 integers
2273 - Sophie Germain prime
2276 - sum of the first 35 primes, centered heptagonal number
2278 - triangular number
2287 - balanced prime
2294 - Mertens function zero
2295 - Mertens function zero
2296 - Mertens function zero
2299 - member of a Ruth-Aaron pair with 2300 (first definition)
2300 - tetrahedral number, member of a Ruth-Aaron pair with 2299 (first definition)
2301 - nonagonal number
2304 - $482$
2306 - Mertens function zero
2309 - primorial prime, Mertens function zero, highly cototient number
2310 - 5th primorial
2311 - primorial prime
2321 - Mertens function zero
2322 - Mertens function zero
2326 - centered pentagonal number
2328 - sum of the totient function for the first 87 integers, the number of groups of order 128, see [1].

2331 - centered cube number
2338 - Mertens function zero
2339 - Sophie Germain prime
2346 - triangular number
2351 - Sophie Germain prime
2352 - pronic number
2357 - Smarandache-Wellin prime
2368 - sum of the totient function for the first 88 integers
2378 - Pell number
2379 - member of the Mian-Chowla sequence
2393 - Sophie Germain prime
2397 - sum of the squares of the first ten primes
2399 - Sophie Germain prime
2400 - perfect score on SAT tests administered after 2005
2401 - $74$ , $492$ , centered octagonal number
2415 - triangular number
2417 - balanced prime
2425 - decagonal number
2427 - sum of the first 36 primes
2437 - cuban prime
2447 - safe prime
2450 - pronic number
2456 - sum of the totient function for the first 89 integers
2458 - centered heptagonal number
2459 - Sophie Germain prime, safe prime
2465 - magic constant of n×n normal magic square and n-Queens Problem for n = 17, Carmichael number
2470 - square pyramidal number
2480 - sum of the totient function for the first 90 integers
2481 - centered pentagonal number
2484 - nonagonal number
2485 - triangular number
2491 - member of Ruth-Aaron pair with 2492 under second definition
2492 - member of Ruth-Aaron pair with 2491 under second definition
2500 - $502$
2501 - Mertens function zero
2502 - Mertens function zero
2510 - member of the Mian-Chowla sequence
2513 - member of the Padovan sequence
2517 - Mertens function zero
2519 - the smallest number when divided by 10 gives a remainder 9; when divided by 9 gives a remainder 8; when divided by 7 gives a remainder 6; and so on until when divided by 2 gives a remainder 1
2520 - highly composite number; smallest number divisible by numbers 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, & 12 ; colossally abundant number; Harshad number in several bases.
2522 - Mertens function zero
2523 - Mertens function zero
2524 - Mertens function zero
2525 - Mertens function zero
2530 - Mertens function zero, Leyland number
2533 - Mertens function zero
2537 - Mertens function zero
2538 - Mertens function zero
2543 - Sophie Germain prime
2549 - Sophie Germain prime
2550 - pronic number
2552 - sum of the totient function for the first 91 integers
2556 - triangular number
2567 - Mertens function zero
2568 - Mertens function zero. Also number of digits in the decimal expansion of 1000!, or the product of all natural numbers from 1 to 1000.
2570 - Mertens function zero
2579 - safe prime
2580 - Keith number
2584 - Fibonacci number, sum of the first 37 primes
2596 - sum of the totient function for the first 92 integers
2600 - tetrahedral number, member of a Ruth-Aaron pair with 2601 (first definition)
- 2600 Hz is the tone used by a blue box to defeat toll charges on long distance telephone calls.
- 2600: The Hacker Quarterly is a magazine named after the above.
- The Atari 2600 was a popular video game console.
2601 - $512$ , member of a Ruth-Aaron pair with 2600 (first definition)
2620 - amicable number with 2924
2626 - decagonal number
2628 - triangular number
2632 - number of consecutive baseball games played by Cal Ripken, Jr.
2641 - centered pentagonal number
2647 - centered heptagonal number
2652 - pronic number
2656 - sum of the totient function for the first 93 integers
2674 - nonagonal number
2677 - balanced prime
2680 - number of 11-Queens Problem solutions
2689 - Mertens function zero, Proth prime
2693 - Sophie Germain prime
2699 - Sophie Germain prime
2701 - triangular number, super-Poulet number
2702 - sum of the totient function for the first 94 integers
2704 - $522$
2728 - Kaprekar number
2729 - highly cototient number
2731 - Wagstaff prime
2736 - octahedral number
2741 - Sophie Germain prime
2744 - $143$
2747 - sum of the first 38 primes
2753 - Sophie Germain prime, Proth prime
2756 - pronic number
2774 - sum of the totient function for the first 95 integers
2775 - triangular number
2780 - member of the Mian-Chowla sequence
2783 - member of a Ruth-Aaron pair with 2784 (first definition)
2784 - member of a Ruth-Aaron pair with 2783 (first definition)
2791 - cuban prime
2806 - centered pentagonal number, sum of the totient function for the first 96 integers
2809 - $532$ , centered octagonal number
2819 - Sophie Germain prime, safe prime
2821 - Carmichael number
2835 - odd abundant number, decagonal number
2843 - centered heptagonal number
2850 - triangular number
2862 - pronic number
2870 - square pyramidal number
2871 - nonagonal number
2872 - tetranacci number
2879 - safe prime
2897 - Markov number
2902 - sum of the totient function for the first 97 integers
2903 - Sophie Germain prime, safe prime, balanced prime
2914 - sum of the first 39 primes
2915 - Lucas-Carmichael number
2916 - $542$
2924 - amicable number with 2620
2925 - magic constant of n×n normal magic square and n-Queens Problem for n = 18, tetrahedral number, member of the Mian-Chowla sequence
2926 - triangular number
2939 - Sophie Germain prime
2944 - sum of the totient function for the first 98 integers
2963 - Sophie Germain prime, safe prime, balanced prime
2965 - greater of 2nd pair of Smith brothers
2969 - Sophie Germain prime
2970 - harmonic divisor number, pronic number
2976 - centered pentagonal number
2997 - chiliagonal number
2999 - safe prime