644562102 has 16 divisors (see below), whose sum is σ = 1290342960. Its totient is φ = 214650912.

The previous prime is 644562077. The next prime is 644562181. The reversal of 644562102 is 201265446.

It is a self number, because there is not a number n which added to its sum of digits gives 644562102.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43833 + ... + 56660.

It is an arithmetic number, because the mean of its divisors is an integer number (80646435).

Almost surely, 2^644562102 is an apocalyptic number.

644562102 is an abundant number, since it is smaller than the sum of its proper divisors (645780858).

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

644562102 is a wasteful number, since it uses less digits than its factorization.

644562102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101567.

The product of its (nonzero) digits is 11520, while the sum is 30.

The square root of 644562102 is about 25388.2276262050. The cubic root of 644562102 is about 863.8166861822.

The spelling of 644562102 in words is "six hundred forty-four million, five hundred sixty-two thousand, one hundred two".