256931740 has 24 divisors (see below), whose sum is σ = 581061600. Its totient is φ = 94867008.

The previous prime is 256931723. The next prime is 256931743. The reversal of 256931740 is 47139652.

It is a self number, because there is not a number n which added to its sum of digits gives 256931740.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256931743) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 493840 + ... + 494359.

It is an arithmetic number, because the mean of its divisors is an integer number (24210900).

Almost surely, 2^256931740 is an apocalyptic number.

256931740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256931740 is an abundant number, since it is smaller than the sum of its proper divisors (324129860).

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

256931740 is a wasteful number, since it uses less digits than its factorization.

256931740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 988221 (or 988219 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 37.

The square root of 256931740 is about 16029.0904295908. The cubic root of 256931740 is about 635.7298240652.

The spelling of 256931740 in words is "two hundred fifty-six million, nine hundred thirty-one thousand, seven hundred forty".