256564055455 has 32 divisors (see below), whose sum is σ = 326653119360. Its totient is φ = 193145971200.

The previous prime is 256564055453. The next prime is 256564055491. The reversal of 256564055455 is 554550465652.

It is not a de Polignac number, because 256564055455 - 2¹ = 256564055453 is a prime.

It is a super-2 number, since 2×256564055455² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256564055453) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1049889 + ... + 1270981.

It is an arithmetic number, because the mean of its divisors is an integer number (10207909980).

Almost surely, 2^256564055455 is an apocalyptic number.

256564055455 is a deficient number, since it is larger than the sum of its proper divisors (70089063905).

256564055455 is a wasteful number, since it uses less digits than its factorization.

256564055455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221331.

The product of its (nonzero) digits is 18000000, while the sum is 52.

The spelling of 256564055455 in words is "two hundred fifty-six billion, five hundred sixty-four million, fifty-five thousand, four hundred fifty-five".