21631504636672 has 144 divisors (see below), whose sum is σ = 53135218321920. Its totient is φ = 8577425424384.

The previous prime is 21631504636667. The next prime is 21631504636733. The reversal of 21631504636672 is 27663640513612.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4220148 + ... + 7814899.

It is an arithmetic number, because the mean of its divisors is an integer number (368994571680).

Almost surely, 2^{21631504636672} is an apocalyptic number.

It is an amenable number.

21631504636672 is an abundant number, since it is smaller than the sum of its proper divisors (31503713685248).

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

21631504636672 is a wasteful number, since it uses less digits than its factorization.

21631504636672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12035146 (or 12035132 counting only the distinct ones).

The product of its (nonzero) digits is 6531840, while the sum is 52.

The spelling of 21631504636672 in words is "twenty-one trillion, six hundred thirty-one billion, five hundred four million, six hundred thirty-six thousand, six hundred seventy-two".