256858506 has 32 divisors (see below), whose sum is σ = 580478400. Its totient is φ = 84167280.

The previous prime is 256858493. The next prime is 256858507. The reversal of 256858506 is 605858652.

256858506 is a `hidden beast` number, since 2 + 5 + 68 + 585 + 0 + 6 = 666.

It is not an unprimeable number, because it can be changed into a prime (256858507) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37125 + ... + 43496.

It is an arithmetic number, because the mean of its divisors is an integer number (18139950).

Almost surely, 2^256858506 is an apocalyptic number.

256858506 is an abundant number, since it is smaller than the sum of its proper divisors (323619894).

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

256858506 is a wasteful number, since it uses less digits than its factorization.

256858506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80691 (or 80685 counting only the distinct ones).

The product of its (nonzero) digits is 576000, while the sum is 45.

The square root of 256858506 is about 16026.8058576873. The cubic root of 256858506 is about 635.6694170195.

It can be divided in two parts, 25685 and 8506, that added together give a triangular number (34191 = T₂₆₁).

The spelling of 256858506 in words is "two hundred fifty-six million, eight hundred fifty-eight thousand, five hundred six".