256564305140 has 48 divisors (see below), whose sum is σ = 632978236800. Its totient is φ = 86119486080.

The previous prime is 256564305131. The next prime is 256564305149. The reversal of 256564305140 is 41503465652.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (256564305131) and next prime (256564305149).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256564305149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44851040 + ... + 44856759.

It is an arithmetic number, because the mean of its divisors is an integer number (13187046600).

Almost surely, 2^256564305140 is an apocalyptic number.

256564305140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256564305140 is an abundant number, since it is smaller than the sum of its proper divisors (376413931660).

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

256564305140 is a wasteful number, since it uses less digits than its factorization.

256564305140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89707832 (or 89707830 counting only the distinct ones).

The product of its (nonzero) digits is 432000, while the sum is 41.

The spelling of 256564305140 in words is "two hundred fifty-six billion, five hundred sixty-four million, three hundred five thousand, one hundred forty".