644010464 has 24 divisors (see below), whose sum is σ = 1268809920. Its totient is φ = 321773056.

The previous prime is 644010431. The next prime is 644010469. The reversal of 644010464 is 464010446.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644010469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43217 + ... + 56175.

It is an arithmetic number, because the mean of its divisors is an integer number (52867080).

Almost surely, 2^644010464 is an apocalyptic number.

It is an amenable number.

644010464 is a deficient number, since it is larger than the sum of its proper divisors (624799456).

644010464 is a wasteful number, since it uses less digits than its factorization.

644010464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14522 (or 14514 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 29.

The square root of 644010464 is about 25377.3612497438. The cubic root of 644010464 is about 863.5701880241.

The spelling of 644010464 in words is "six hundred forty-four million, ten thousand, four hundred sixty-four".