656981863944 has 64 divisors (see below), whose sum is σ = 1898181993600. Its totient is φ = 185600008704.

The previous prime is 656981863939. The next prime is 656981863969. The reversal of 656981863944 is 449368189656.

656981863944 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 21954747 + ... + 21984650.

It is an arithmetic number, because the mean of its divisors is an integer number (29659093650).

Almost surely, 2^656981863944 is an apocalyptic number.

It is an amenable number.

656981863944 is an abundant number, since it is smaller than the sum of its proper divisors (1241200129656).

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

656981863944 is a wasteful number, since it uses less digits than its factorization.

656981863944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43939502 (or 43939498 counting only the distinct ones).

The product of its digits is 268738560, while the sum is 69.

The spelling of 656981863944 in words is "six hundred fifty-six billion, nine hundred eighty-one million, eight hundred sixty-three thousand, nine hundred forty-four".