656537923899 has 48 divisors (see below), whose sum is σ = 1123984723680. Its totient is φ = 364043473920.

The previous prime is 656537923891. The next prime is 656537923901. The reversal of 656537923899 is 998329735656.

656537923899 is a `hidden beast` number, since 6 + 5 + 6 + 537 + 9 + 2 + 3 + 89 + 9 = 666.

It is not a de Polignac number, because 656537923899 - 2³ = 656537923891 is a prime.

It is not an unprimeable number, because it can be changed into a prime (656537923891) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2111784 + ... + 2402645.

It is an arithmetic number, because the mean of its divisors is an integer number (23416348410).

Almost surely, 2^656537923899 is an apocalyptic number.

656537923899 is a deficient number, since it is larger than the sum of its proper divisors (467446799781).

656537923899 is a wasteful number, since it uses less digits than its factorization.

656537923899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4514572 (or 4514569 counting only the distinct ones).

The product of its digits is 661348800, while the sum is 72.

The spelling of 656537923899 in words is "six hundred fifty-six billion, five hundred thirty-seven million, nine hundred twenty-three thousand, eight hundred ninety-nine".