21625656402 has 64 divisors (see below), whose sum is σ = 49802711040. Its totient is φ = 6132357504.

The previous prime is 21625656359. The next prime is 21625656419. The reversal of 21625656402 is 20465652612.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3138453 + ... + 3145335.

It is an arithmetic number, because the mean of its divisors is an integer number (778167360).

Almost surely, 2^21625656402 is an apocalyptic number.

21625656402 is an abundant number, since it is smaller than the sum of its proper divisors (28177054638).

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

21625656402 is a wasteful number, since it uses less digits than its factorization.

21625656402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7447.

The product of its (nonzero) digits is 172800, while the sum is 39.

The spelling of 21625656402 in words is "twenty-one billion, six hundred twenty-five million, six hundred fifty-six thousand, four hundred two".