256275921 has 32 divisors (see below), whose sum is σ = 380160000. Its totient is φ = 152268480.

The previous prime is 256275919. The next prime is 256275931. The reversal of 256275921 is 129572652.

It is not a de Polignac number, because 256275921 - 2¹ = 256275919 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 256275921.

It is not an unprimeable number, because it can be changed into a prime (256275931) 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, 513330 + ... + 513828.

It is an arithmetic number, because the mean of its divisors is an integer number (11880000).

Almost surely, 2^256275921 is an apocalyptic number.

It is an amenable number.

256275921 is a deficient number, since it is larger than the sum of its proper divisors (123884079).

256275921 is a wasteful number, since it uses less digits than its factorization.

256275921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 789.

The product of its digits is 75600, while the sum is 39.

The square root of 256275921 is about 16008.6202091248. The cubic root of 256275921 is about 635.1884624642.

The spelling of 256275921 in words is "two hundred fifty-six million, two hundred seventy-five thousand, nine hundred twenty-one".