256304565405 has 48 divisors (see below), whose sum is σ = 507895564800. Its totient is φ = 117128934144.

The previous prime is 256304565389. The next prime is 256304565409. The reversal of 256304565405 is 504565403652.

256304565405 is a `hidden beast` number, since 2 + 5 + 63 + 0 + 45 + 6 + 540 + 5 = 666.

It is not a de Polignac number, because 256304565405 - 2⁴ = 256304565389 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 (256304565409) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 827004 + ... + 1093866.

It is an arithmetic number, because the mean of its divisors is an integer number (10581157600).

Almost surely, 2^256304565405 is an apocalyptic number.

It is an amenable number.

256304565405 is a deficient number, since it is larger than the sum of its proper divisors (251590999395).

256304565405 is a wasteful number, since it uses less digits than its factorization.

256304565405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269930 (or 269927 counting only the distinct ones).

The product of its (nonzero) digits is 2160000, while the sum is 45.

The spelling of 256304565405 in words is "two hundred fifty-six billion, three hundred four million, five hundred sixty-five thousand, four hundred five".