256279074721 has 4 divisors (see below), whose sum is σ = 256549697712. Its totient is φ = 256008451732.

The previous prime is 256279074677. The next prime is 256279074767. The reversal of 256279074721 is 127470972652.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 256279074721 - 2¹⁷ = 256278943649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256279074521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 135310075 + ... + 135311968.

It is an arithmetic number, because the mean of its divisors is an integer number (64137424428).

Almost surely, 2^256279074721 is an apocalyptic number.

It is an amenable number.

256279074721 is a deficient number, since it is larger than the sum of its proper divisors (270622991).

256279074721 is an equidigital number, since it uses as much as digits as its factorization.

256279074721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 270622990.

The product of its (nonzero) digits is 2963520, while the sum is 52.

The spelling of 256279074721 in words is "two hundred fifty-six billion, two hundred seventy-nine million, seventy-four thousand, seven hundred twenty-one".