256215564045 has 128 divisors (see below), whose sum is σ = 542294016000. Its totient is φ = 112307523840.

The previous prime is 256215564041. The next prime is 256215564047. The reversal of 256215564045 is 540465512652.

256215564045 is a `hidden beast` number, since 2 + 56 + 2 + 1 + 556 + 4 + 0 + 45 = 666.

It is not a de Polignac number, because 256215564045 - 2² = 256215564041 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256215564041) 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 127 ways as a sum of consecutive naturals, for example, 3153036 + ... + 3233274.

It is an arithmetic number, because the mean of its divisors is an integer number (4236672000).

Almost surely, 2^256215564045 is an apocalyptic number.

It is an amenable number.

256215564045 is an abundant number, since it is smaller than the sum of its proper divisors (286078451955).

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

256215564045 is a wasteful number, since it uses less digits than its factorization.

256215564045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80400 (or 80394 counting only the distinct ones).

The product of its (nonzero) digits is 1440000, while the sum is 45.

The spelling of 256215564045 in words is "two hundred fifty-six billion, two hundred fifteen million, five hundred sixty-four thousand, forty-five".