256401 has 12 divisors (see below), whose sum is σ = 382720. Its totient is φ = 165240.

The previous prime is 256393. The next prime is 256423. The reversal of 256401 is 104652.

It is a happy number.

256401 is a `hidden beast` number, since 25 + 640 + 1 = 666.

It is not a de Polignac number, because 256401 - 2³ = 256393 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 256401.

It is not an unprimeable number, because it can be changed into a prime (256441) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 181 + ... + 738.

2²⁵⁶⁴⁰¹ is an apocalyptic number.

It is an amenable number.

256401 is a deficient number, since it is larger than the sum of its proper divisors (126319).

256401 is a wasteful number, since it uses less digits than its factorization.

256401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 956 (or 953 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 256401 is about 506.3605434866. The cubic root of 256401 is about 63.5291783155.

The spelling of 256401 in words is "two hundred fifty-six thousand, four hundred one".