40,000 (forty thousand) is the natural number that comes after 39,999 and before 40,001. It is the square of 200.

Selected numbers in the range 40001–49999

40001 to 40999

* 40320 = smallest

factorial In mathematics, the factorial of a non-negative denoted is the product of all positive integers less than or equal The factorial also equals the product of n with the next smaller factorial: \begin n! &= n \times (n-1) \times (n-2) \t ...

(8!) that is not a

highly composite number __FORCETOC__ A highly composite number is a positive integer with more divisors than any smaller positive integer has. The related concept of largely composite number refers to a positive integer which has at least as many divisors as any smaller ...

* 40425 =

square pyramidal number In mathematics, a pyramid number, or square pyramidal number, is a natural number that counts the number of stacked spheres in a pyramid with a square base. The study of these numbers goes back to Archimedes and Fibonacci. They are part of a broa ...

* 40585 = largest

factorion In number theory, a factorion in a given number base b is a natural number that equals the sum of the factorials of its digits. The name factorion was coined by the author Clifford A. Pickover. Definition Let n be a natural number. For a base b > ...

* 40678 = pentagonal pyramidal number * 40804 = palindromic square

41000 to 41999

* 41041 = Carmichael number * 41472 = 3- smooth number * 41586 = Large Schröder number * 41616 =

triangular square number In mathematics, a square triangular number (or triangular square number) is a number which is both a triangular number and a perfect square. There are infinitely many square triangular numbers; the first few are: :0, 1, 36, , , , , , , Expl ...

* 41835 = Motzkin number * 41841 = 1/41841 = 0.0000239 is a repeating decimal with period 7.

42000 to 42999

* 42680 = octahedral number * 42875 = 35³ * 42925 =

43000 to 43999

* 43261 = Markov number * 43390 = number of primes

\leq 2^

. * 43560 = pentagonal pyramidal number * 43691 = Wagstaff prime * 43777 = smallest member of a prime sextuplet

44000 to 44999

* 44044 = palindrome of 79 after 6 iterations of the "reverse and add" iterative process * 44100 = sum of the cubes of the first 20 positive integers.

44,100 Hz In digital audio, 44,100 Hz (alternately represented as 44.1 kHz) is a common sampling frequency. Analog audio is often recorded by sampling it 44,100 times per second, and then these samples are used to reconstruct the audio signal w ...

is a common sampling frequency in digital audio (and is the standard for compact discs). * 44444 = repdigit * 44721 = smallest positive integer such that the expression − ≤ 10⁻⁹ * 44944 = palindromic square

45000 to 45999

* 45360 =

; first number to have 100 factors (including one and itself)

46000 to 46999

* 46233 = sum of the first eight factorials * 46368 = Fibonacci number * 46656 = 36, 6⁶, 3- smooth number * 46657 = Carmichael number *

46664 46664 was a series of AIDS benefit concerts played in honour of Nelson Mandela by South African and foreign musicians between 2003 and 2008. Origin The second time that Mandela was imprisoned on Robben Island was in 1964, and he was the 466th ...

Nelson Mandela Nelson Rolihlahla Mandela (; ; 18 July 1918 – 5 December 2013) was a South African Internal resistance to apartheid, anti-apartheid activist who served as the President of South Africa, first president of South Africa from 1994 to 1 ...

's prisoner number

47000 to 47999

* 47058 = primary pseudoperfect number * 47160 = 10-th derivative of x^x at x=1 * 47321/33461 ≈ √2

48000 to 48999

49000 to 49999

* 49151 = Woodall number * 49152 = 3- smooth number * 49726 = pentagonal pyramidal number

References

{{Integers, 10 40000