644003004 has 24 divisors (see below), whose sum is σ = 1510230400. Its totient is φ = 213588144.

The previous prime is 644002991. The next prime is 644003011. The reversal of 644003004 is 400300446.

644003004 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×644003004² = 829479738322048032, which contains 22 as substring.

It is a congruent number.

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, 132454 + ... + 137229.

Almost surely, 2^644003004 is an apocalyptic number.

It is an amenable number.

644003004 is an abundant number, since it is smaller than the sum of its proper divisors (866227396).

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

644003004 is a wasteful number, since it uses less digits than its factorization.

644003004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 269889 (or 269887 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 21.

The square root of 644003004 is about 25377.2142679215. The cubic root of 644003004 is about 863.5668535759.

The spelling of 644003004 in words is "six hundred forty-four million, three thousand, four".