656257985 has 8 divisors (see below), whose sum is σ = 789289920. Its totient is φ = 523819504.

The previous prime is 656257969. The next prime is 656257999. The reversal of 656257985 is 589752656.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 656257985 - 2⁴ = 656257969 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 145925 + ... + 150354.

It is an arithmetic number, because the mean of its divisors is an integer number (98661240).

Almost surely, 2^656257985 is an apocalyptic number.

It is an amenable number.

656257985 is a deficient number, since it is larger than the sum of its proper divisors (133031935).

656257985 is a wasteful number, since it uses less digits than its factorization.

656257985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 296727.

The product of its digits is 4536000, while the sum is 53.

The square root of 656257985 is about 25617.5327656666. The cubic root of 656257985 is about 869.0101857880.

The spelling of 656257985 in words is "six hundred fifty-six million, two hundred fifty-seven thousand, nine hundred eighty-five".