256745213732556 has 72 divisors (see below), whose sum is σ = 683780946401280. Its totient is φ = 81002847423456.

The previous prime is 256745213732503. The next prime is 256745213732569. The reversal of 256745213732556 is 655237312547652.

256745213732556 is a `hidden beast` number, since 2 + 5 + 6 + 7 + 4 + 5 + 2 + 1 + 3 + 73 + 2 + 556 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 256745213732493 and 256745213732502.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 171914496 + ... + 173401511.

Almost surely, 2^{256745213732556} is an apocalyptic number.

It is an amenable number.

256745213732556 is an abundant number, since it is smaller than the sum of its proper divisors (427035732668724).

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

256745213732556 is a wasteful number, since it uses less digits than its factorization.

256745213732556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 345317123 (or 345317118 counting only the distinct ones).

The product of its digits is 317520000, while the sum is 63.

The spelling of 256745213732556 in words is "two hundred fifty-six trillion, seven hundred forty-five billion, two hundred thirteen million, seven hundred thirty-two thousand, five hundred fifty-six".