641695656 has 32 divisors (see below), whose sum is σ = 1833416640. Its totient is φ = 183341568.

The previous prime is 641695609. The next prime is 641695669. The reversal of 641695656 is 656596146.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1909641 + ... + 1909976.

It is an arithmetic number, because the mean of its divisors is an integer number (57294270).

Almost surely, 2^641695656 is an apocalyptic number.

It is an amenable number.

641695656 is an abundant number, since it is smaller than the sum of its proper divisors (1191720984).

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

641695656 is a wasteful number, since it uses less digits than its factorization.

641695656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3819633 (or 3819629 counting only the distinct ones).

The product of its digits is 1166400, while the sum is 48.

The square root of 641695656 is about 25331.7124569185. The cubic root of 641695656 is about 862.5342840394.

The spelling of 641695656 in words is "six hundred forty-one million, six hundred ninety-five thousand, six hundred fifty-six".