644352204 has 12 divisors (see below), whose sum is σ = 1503488504. Its totient is φ = 214784064.

The previous prime is 644352197. The next prime is 644352209. The reversal of 644352204 is 402253446.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (644352209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26847997 + ... + 26848020.

Almost surely, 2^644352204 is an apocalyptic number.

It is an amenable number.

644352204 is an abundant number, since it is smaller than the sum of its proper divisors (859136300).

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

644352204 is a wasteful number, since it uses less digits than its factorization.

644352204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53696024 (or 53696022 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 30.

The square root of 644352204 is about 25384.0935233071. The cubic root of 644352204 is about 863.7229103308.

The spelling of 644352204 in words is "six hundred forty-four million, three hundred fifty-two thousand, two hundred four".