646644304 has 10 divisors (see below), whose sum is σ = 1252873370. Its totient is φ = 323322144.

The previous prime is 646644253. The next prime is 646644337. The reversal of 646644304 is 403446646.

It can be written as a sum of positive squares in only one way, i.e., 642723904 + 3920400 = 25352^2 + 1980^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20207619 + ... + 20207650.

It is an arithmetic number, because the mean of its divisors is an integer number (125287337).

Almost surely, 2^646644304 is an apocalyptic number.

It is an amenable number.

646644304 is a deficient number, since it is larger than the sum of its proper divisors (606229066).

646644304 is a wasteful number, since it uses less digits than its factorization.

646644304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40415277 (or 40415271 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 37.

The square root of 646644304 is about 25429.2017963600. The cubic root of 646644304 is about 864.7458480167.

The spelling of 646644304 in words is "six hundred forty-six million, six hundred forty-four thousand, three hundred four".