256984665 has 96 divisors (see below), whose sum is σ = 513558144. Its totient is φ = 109025280.

The previous prime is 256984649. The next prime is 256984687. The reversal of 256984665 is 566489652.

256984665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 256984665 - 2⁴ = 256984649 is a prime.

It is a super-2 number, since 2×256984665² = 132082236090324450, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

Its product of digits (3110400) is a multiple of the sum of its prime divisors (320).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1636767 + ... + 1636923.

It is an arithmetic number, because the mean of its divisors is an integer number (5349564).

Almost surely, 2^256984665 is an apocalyptic number.

It is an amenable number.

256984665 is a deficient number, since it is larger than the sum of its proper divisors (256573479).

256984665 is a wasteful number, since it uses less digits than its factorization.

256984665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 327 (or 320 counting only the distinct ones).

The product of its digits is 3110400, while the sum is 51.

The square root of 256984665 is about 16030.7412492374. The cubic root of 256984665 is about 635.7734720927.

The spelling of 256984665 in words is "two hundred fifty-six million, nine hundred eighty-four thousand, six hundred sixty-five".