644964412 has 6 divisors (see below), whose sum is σ = 1128687728. Its totient is φ = 322482204.

The previous prime is 644964403. The next prime is 644964421. The reversal of 644964412 is 214469446.

It is an interprime number because it is at equal distance from previous prime (644964403) and next prime (644964421).

It is a congruent number.

It is an unprimeable number.

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, 80620548 + ... + 80620555.

Almost surely, 2^644964412 is an apocalyptic number.

It is an amenable number.

644964412 is a deficient number, since it is larger than the sum of its proper divisors (483723316).

644964412 is a wasteful number, since it uses less digits than its factorization.

644964412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161241107 (or 161241105 counting only the distinct ones).

The product of its digits is 165888, while the sum is 40.

The square root of 644964412 is about 25396.1495506701. The cubic root of 644964412 is about 863.9963687976.

The spelling of 644964412 in words is "six hundred forty-four million, nine hundred sixty-four thousand, four hundred twelve".