644842604 has 48 divisors (see below), whose sum is σ = 1311061248. Its totient is φ = 271812288.

The previous prime is 644842571. The next prime is 644842609. The reversal of 644842604 is 406248446.

644842604 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (644842609) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 680459 + ... + 681405.

It is an arithmetic number, because the mean of its divisors is an integer number (27313776).

Almost surely, 2^644842604 is an apocalyptic number.

It is an amenable number.

644842604 is an abundant number, since it is smaller than the sum of its proper divisors (666218644).

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

644842604 is a wasteful number, since it uses less digits than its factorization.

644842604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1334 (or 1332 counting only the distinct ones).

The product of its (nonzero) digits is 147456, while the sum is 38.

The square root of 644842604 is about 25393.7512786118. The cubic root of 644842604 is about 863.9419739123.

The spelling of 644842604 in words is "six hundred forty-four million, eight hundred forty-two thousand, six hundred four".