257720564 has 24 divisors (see below), whose sum is σ = 469997640. Its totient is φ = 123501056.

The previous prime is 257720563. The next prime is 257720621. The reversal of 257720564 is 465027752.

It is a happy number.

257720564 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 85008400 + 172712164 = 9220^2 + 13142^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257720563) 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, 7784 + ... + 24000.

It is an arithmetic number, because the mean of its divisors is an integer number (19583235).

Almost surely, 2^257720564 is an apocalyptic number.

It is an amenable number.

257720564 is a deficient number, since it is larger than the sum of its proper divisors (212277076).

257720564 is a wasteful number, since it uses less digits than its factorization.

257720564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16387 (or 16385 counting only the distinct ones).

The product of its (nonzero) digits is 117600, while the sum is 38.

The square root of 257720564 is about 16053.6775849025. The cubic root of 257720564 is about 636.3797588272.

The spelling of 257720564 in words is "two hundred fifty-seven million, seven hundred twenty thousand, five hundred sixty-four".