40,000

Selected numbers in the range 40001–49999

40001 to 40999

• 40320 – smallest factorial that is not a highly composite number
• 40425 – square pyramidal number
• 40585 – largest factorion
• 40678 – pentagonal pyramidal number
• 40804 – palindromic square

  41000 to 41999

• 41041 – Carmichael number
• 41472 – 3-smooth number
• 41616 – triangular square number
• 41835 – Motzkin number

  42000 to 42999

• 42680 – octahedral number
• 42875 – 35³
• 42925 – square pyramidal number

  43000 to 43999

• 43261 – Markov number
• 43560 – pentagonal pyramidal number
• 43691 – Wagstaff prime

  44000 to 44999

• 44100 – sum of the cubes of the first 20 positive integers, sampling rate of Red Book-compliant audio compact disks
• 44444 – repdigit
• 44721 – When n > 44721, the expression − drops down to fractions of a billionth. The corresponding sum in the Leibniz formula for pi is 0.785386986.
• 44944 – palindromic square

  45000 to 45999

• 45360 – highly composite number; first number to have 100 factors

  46000 to 46999

• 46233 – sum of the first eight factorials
• 46368 – Fibonacci number
• 46656 – 36, 6⁶, 3-smooth number
• 46657 – Carmichael number
• 46664 – Nelson Mandela's prisoner number

  47000 to 47999

• 47058 – primary pseudoperfect number

  48000 to 48999

49000 to 49999

• 49151 – Woodall number
• 49152 – 3-smooth number
• 49726 – pentagonal pyramidal number