256404621 has 32 divisors (see below), whose sum is σ = 390666240. Its totient is φ = 148068800.

The previous prime is 256404607. The next prime is 256404623. The reversal of 256404621 is 126404652.

256404621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 256404621 - 2¹³ = 256396429 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256404623) 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, 272011 + ... + 272951.

It is an arithmetic number, because the mean of its divisors is an integer number (12208320).

Almost surely, 2^256404621 is an apocalyptic number.

It is an amenable number.

256404621 is a deficient number, since it is larger than the sum of its proper divisors (134261619).

256404621 is a wasteful number, since it uses less digits than its factorization.

256404621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1337.

The product of its (nonzero) digits is 11520, while the sum is 30.

The square root of 256404621 is about 16012.6394139130. The cubic root of 256404621 is about 635.2947737582.

The spelling of 256404621 in words is "two hundred fifty-six million, four hundred four thousand, six hundred twenty-one".