256940928 has 96 divisors (see below), whose sum is σ = 764969400. Its totient is φ = 82682880.

The previous prime is 256940921. The next prime is 256940969. The reversal of 256940928 is 829049652.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256940921) 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, 29563 + ... + 37253.

Almost surely, 2^256940928 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256940928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (382484700).

256940928 is an abundant number, since it is smaller than the sum of its proper divisors (508028472).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256940928 is a wasteful number, since it uses less digits than its factorization.

256940928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7740 (or 7725 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The square root of 256940928 is about 16029.3770309392. The cubic root of 256940928 is about 635.7374019741.

The spelling of 256940928 in words is "two hundred fifty-six million, nine hundred forty thousand, nine hundred twenty-eight".