644716802 has 16 divisors (see below), whose sum is σ = 990876480. Its totient is φ = 314444592.

The previous prime is 644716783. The next prime is 644716883. The reversal of 644716802 is 208617446.

It is a super-2 number, since 2×644716802² = 831319509562214408, which contains 22 as substring.

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 in 7 ways as a sum of consecutive naturals, for example, 66224 + ... + 75332.

It is an arithmetic number, because the mean of its divisors is an integer number (61929780).

Almost surely, 2^644716802 is an apocalyptic number.

644716802 is a deficient number, since it is larger than the sum of its proper divisors (346159678).

644716802 is a wasteful number, since it uses less digits than its factorization.

644716802 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9977.

The product of its (nonzero) digits is 64512, while the sum is 38.

The square root of 644716802 is about 25391.2741310868. The cubic root of 644716802 is about 863.8857882653.

The spelling of 644716802 in words is "six hundred forty-four million, seven hundred sixteen thousand, eight hundred two".