644422002 has 16 divisors (see below), whose sum is σ = 1472964672. Its totient is φ = 184120560.

The previous prime is 644421997. The next prime is 644422067. The reversal of 644422002 is 200224446.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7671649 + ... + 7671732.

It is an arithmetic number, because the mean of its divisors is an integer number (92060292).

Almost surely, 2^644422002 is an apocalyptic number.

644422002 is an abundant number, since it is smaller than the sum of its proper divisors (828542670).

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

644422002 is a wasteful number, since it uses less digits than its factorization.

644422002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15343393.

The product of its (nonzero) digits is 3072, while the sum is 24.

The square root of 644422002 is about 25385.4683234326. The cubic root of 644422002 is about 863.7540961505.

Adding to 644422002 its reverse (200224446), we get a palindrome (844646448).

The spelling of 644422002 in words is "six hundred forty-four million, four hundred twenty-two thousand, two".