644003084 has 6 divisors (see below), whose sum is σ = 1127005404. Its totient is φ = 322001540.

The previous prime is 644003077. The next prime is 644003089. The reversal of 644003084 is 480300446.

It is a super-2 number, since 2×644003084² = 829479944403022112, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (644003089) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80500382 + ... + 80500389.

It is an arithmetic number, because the mean of its divisors is an integer number (187834234).

Almost surely, 2^644003084 is an apocalyptic number.

It is an amenable number.

644003084 is a deficient number, since it is larger than the sum of its proper divisors (483002320).

644003084 is a wasteful number, since it uses less digits than its factorization.

644003084 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161000775 (or 161000773 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 29.

The square root of 644003084 is about 25377.2158441386. The cubic root of 644003084 is about 863.5668893342.

The spelling of 644003084 in words is "six hundred forty-four million, three thousand, eighty-four".