636725664 has 48 divisors (see below), whose sum is σ = 1857119040. Its totient is φ = 212241600.

The previous prime is 636725659. The next prime is 636725689. The reversal of 636725664 is 466527636.

636725664 is a `hidden beast` number, since 636 + 7 + 2 + 5 + 6 + 6 + 4 = 666.

636725664 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (48).

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, 367612 + ... + 369339.

It is an arithmetic number, because the mean of its divisors is an integer number (38689980).

Almost surely, 2^636725664 is an apocalyptic number.

It is an amenable number.

636725664 is an abundant number, since it is smaller than the sum of its proper divisors (1220393376).

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

636725664 is a wasteful number, since it uses less digits than its factorization.

636725664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 736970 (or 736956 counting only the distinct ones).

The product of its digits is 1088640, while the sum is 45.

The square root of 636725664 is about 25233.4235489360. The cubic root of 636725664 is about 860.3017077346.

The spelling of 636725664 in words is "six hundred thirty-six million, seven hundred twenty-five thousand, six hundred sixty-four".