644516332 has 12 divisors (see below), whose sum is σ = 1136514456. Its totient is φ = 319797920.

The previous prime is 644516303. The next prime is 644516371. The reversal of 644516332 is 233615446.

644516332 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 614473 + ... + 615520.

It is an arithmetic number, because the mean of its divisors is an integer number (94709538).

Almost surely, 2^644516332 is an apocalyptic number.

It is an amenable number.

644516332 is a deficient number, since it is larger than the sum of its proper divisors (491998124).

644516332 is a wasteful number, since it uses less digits than its factorization.

644516332 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1230128 (or 1230126 counting only the distinct ones).

The product of its digits is 51840, while the sum is 34.

The square root of 644516332 is about 25387.3262081693. The cubic root of 644516332 is about 863.7962393157.

It can be divided in two parts, 644516 and 332, that multiplied together give a palindrome (213979312).

The spelling of 644516332 in words is "six hundred forty-four million, five hundred sixteen thousand, three hundred thirty-two".