644010624 has 96 divisors (see below), whose sum is σ = 1950811200. Its totient is φ = 203364864.

The previous prime is 644010623. The next prime is 644010671. The reversal of 644010624 is 426010446.

644010624 is a `hidden beast` number, since 644 + 0 + 10 + 6 + 2 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (96).

It is not an unprimeable number, because it can be changed into a prime (644010623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7177 + ... + 36599.

It is an arithmetic number, because the mean of its divisors is an integer number (20320950).

Almost surely, 2^644010624 is an apocalyptic number.

644010624 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 644010624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (975405600).

644010624 is an abundant number, since it is smaller than the sum of its proper divisors (1306800576).

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

644010624 is a wasteful number, since it uses less digits than its factorization.

644010624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29462 (or 29447 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 644010624 is about 25377.3644021597. The cubic root of 644010624 is about 863.5702595401.

The spelling of 644010624 in words is "six hundred forty-four million, ten thousand, six hundred twenty-four".