256560465656 has 64 divisors (see below), whose sum is σ = 528406610400. Its totient is φ = 115814617600.

The previous prime is 256560465613. The next prime is 256560465703. The reversal of 256560465656 is 656564065652.

It is a congruent number.

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, 14316830 + ... + 14334738.

Almost surely, 2^256560465656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256560465656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (264203305200).

256560465656 is an abundant number, since it is smaller than the sum of its proper divisors (271846144744).

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

256560465656 is a wasteful number, since it uses less digits than its factorization.

256560465656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19040 (or 19036 counting only the distinct ones).

The product of its (nonzero) digits is 38880000, while the sum is 56.

The spelling of 256560465656 in words is "two hundred fifty-six billion, five hundred sixty million, four hundred sixty-five thousand, six hundred fifty-six".