644025372 has 24 divisors (see below), whose sum is σ = 1551201792. Its totient is φ = 207750000.

The previous prime is 644025329. The next prime is 644025377. The reversal of 644025372 is 273520446.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644025377) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 865254 + ... + 865997.

It is an arithmetic number, because the mean of its divisors is an integer number (64633408).

Almost surely, 2^644025372 is an apocalyptic number.

644025372 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

644025372 is an abundant number, since it is smaller than the sum of its proper divisors (907176420).

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

644025372 is a wasteful number, since it uses less digits than its factorization.

644025372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1731289 (or 1731287 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 33.

The square root of 644025372 is about 25377.6549744061. The cubic root of 644025372 is about 863.5768514795.

The spelling of 644025372 in words is "six hundred forty-four million, twenty-five thousand, three hundred seventy-two".