21131111230400 has 84 divisors (see below), whose sum is σ = 51996722778000. Its totient is φ = 8452284825600.

The previous prime is 21131111230387. The next prime is 21131111230429. The reversal of 21131111230400 is 403211113112.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 121882976 + ... + 122056224.

It is an arithmetic number, because the mean of its divisors is an integer number (619008604500).

Almost surely, 2^{21131111230400} is an apocalyptic number.

21131111230400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21131111230400 is an abundant number, since it is smaller than the sum of its proper divisors (30865611547600).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21131111230400 is a wasteful number, since it uses less digits than its factorization.

21131111230400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249502 (or 249487 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 20.

Adding to 21131111230400 its reverse (403211113112), we get a palindrome (21534322343512).

The spelling of 21131111230400 in words is "twenty-one trillion, one hundred thirty-one billion, one hundred eleven million, two hundred thirty thousand, four hundred".