644607512 has 16 divisors (see below), whose sum is σ = 1209120000. Its totient is φ = 322175520.

The previous prime is 644607511. The next prime is 644607517. The reversal of 644607512 is 215706446.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644607511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7337 + ... + 36647.

It is an arithmetic number, because the mean of its divisors is an integer number (75570000).

Almost surely, 2^644607512 is an apocalyptic number.

It is an amenable number.

644607512 is a deficient number, since it is larger than the sum of its proper divisors (564512488).

644607512 is a wasteful number, since it uses less digits than its factorization.

644607512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32066 (or 32062 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 35.

The square root of 644607512 is about 25389.1219225872. The cubic root of 644607512 is about 863.8369712690.

The spelling of 644607512 in words is "six hundred forty-four million, six hundred seven thousand, five hundred twelve".