656752872854921 has 16 divisors (see below), whose sum is σ = 664955957836800. Its totient is φ = 648612529491648.

The previous prime is 656752872854909. The next prime is 656752872854951. The reversal of 656752872854921 is 129458278257656.

It is a cyclic number.

It is not a de Polignac number, because 656752872854921 - 2¹⁰ = 656752872853897 is a prime.

It is a super-2 number, since 2×656752872854921² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (656752872854951) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 392351 + ... + 36244443.

It is an arithmetic number, because the mean of its divisors is an integer number (41559747364800).

Almost surely, 2^{656752872854921} is an apocalyptic number.

It is an amenable number.

656752872854921 is a deficient number, since it is larger than the sum of its proper divisors (8203084981879).

656752872854921 is a wasteful number, since it uses less digits than its factorization.

656752872854921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35852968.

The product of its digits is 4064256000, while the sum is 77.

The spelling of 656752872854921 in words is "six hundred fifty-six trillion, seven hundred fifty-two billion, eight hundred seventy-two million, eight hundred fifty-four thousand, nine hundred twenty-one".