656649946656 has 144 divisors (see below), whose sum is σ = 2084482239840. Its totient is φ = 194357237760.

The previous prime is 656649946627. The next prime is 656649946681.

656649946656 is a `hidden beast` number, since 6 + 56 + 64 + 9 + 9 + 466 + 56 = 666.

656649946656 is nontrivially palindromic in base 10.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2273961 + ... + 2546408.

It is an arithmetic number, because the mean of its divisors is an integer number (14475571110).

Almost surely, 2^656649946656 is an apocalyptic number.

656649946656 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

656649946656 is an abundant number, since it is smaller than the sum of its proper divisors (1427832293184).

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

656649946656 is a wasteful number, since it uses less digits than its factorization.

656649946656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4820439 (or 4820428 counting only the distinct ones).

The product of its digits is 1511654400, while the sum is 72.

The spelling of 656649946656 in words is "six hundred fifty-six billion, six hundred forty-nine million, nine hundred forty-six thousand, six hundred fifty-six".