21031123132100 has 72 divisors (see below), whose sum is σ = 46874137212168. Its totient is φ = 8184535142400.

The previous prime is 21031123132093. The next prime is 21031123132189. The reversal of 21031123132100 is 123132113012.

It is a happy number.

It can be written as a sum of positive squares in 12 ways, for example, as 8457673771264 + 12573449360836 = 2908208^2 + 3545906^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 57140660 + ... + 57507540.

Almost surely, 2^{21031123132100} is an apocalyptic number.

21031123132100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21031123132100 is an abundant number, since it is smaller than the sum of its proper divisors (25843014080068).

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

21031123132100 is a wasteful number, since it uses less digits than its factorization.

21031123132100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 382425 (or 382418 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 20.

Adding to 21031123132100 its reverse (123132113012), we get a palindrome (21154255245112).

The spelling of 21031123132100 in words is "twenty-one trillion, thirty-one billion, one hundred twenty-three million, one hundred thirty-two thousand, one hundred".