656857055879 has 2 divisors, whose sum is σ = 656857055880. Its totient is φ = 656857055878.

The previous prime is 656857055873. The next prime is 656857055917. The reversal of 656857055879 is 978550758656.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 656857055879 - 2⁴ = 656857055863 is a prime.

It is a super-2 number, since 2×656857055879² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (656857055873) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328428527939 + 328428527940.

It is an arithmetic number, because the mean of its divisors is an integer number (328428527940).

Almost surely, 2^656857055879 is an apocalyptic number.

656857055879 is a deficient number, since it is larger than the sum of its proper divisors (1).

656857055879 is an equidigital number, since it uses as much as digits as its factorization.

656857055879 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 635040000, while the sum is 71.

The spelling of 656857055879 in words is "six hundred fifty-six billion, eight hundred fifty-seven million, fifty-five thousand, eight hundred seventy-nine".