644511336 has 64 divisors (see below), whose sum is σ = 1921536000. Its totient is φ = 176138688.

The previous prime is 644511311. The next prime is 644511353. The reversal of 644511336 is 633115446.

644511336 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 644511297 and 644511306.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 79536 + ... + 87263.

It is an arithmetic number, because the mean of its divisors is an integer number (30024000).

Almost surely, 2^644511336 is an apocalyptic number.

It is an amenable number.

644511336 is an abundant number, since it is smaller than the sum of its proper divisors (1277024664).

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

644511336 is a wasteful number, since it uses less digits than its factorization.

644511336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166838 (or 166834 counting only the distinct ones).

The product of its digits is 25920, while the sum is 33.

The square root of 644511336 is about 25387.2278124257. The cubic root of 644511336 is about 863.7940073903.

The spelling of 644511336 in words is "six hundred forty-four million, five hundred eleven thousand, three hundred thirty-six".