256640564247510 has 32 divisors (see below), whose sum is σ = 648355109679360. Its totient is φ = 64835510967648.

The previous prime is 256640564247499. The next prime is 256640564247577. The reversal of 256640564247510 is 15742465046652.

It is a Harshad number since it is a multiple of its sum of digits (57).

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, 225123301402 + ... + 225123302541.

It is an arithmetic number, because the mean of its divisors is an integer number (20261097177480).

Almost surely, 2^{256640564247510} is an apocalyptic number.

256640564247510 is an abundant number, since it is smaller than the sum of its proper divisors (391714545431850).

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

256640564247510 is a wasteful number, since it uses less digits than its factorization.

256640564247510 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 450246603972.

The product of its (nonzero) digits is 48384000, while the sum is 57.

The spelling of 256640564247510 in words is "two hundred fifty-six trillion, six hundred forty billion, five hundred sixty-four million, two hundred forty-seven thousand, five hundred ten".