644377446 has 48 divisors (see below), whose sum is σ = 1436909760. Its totient is φ = 208580400.

The previous prime is 644377441. The next prime is 644377463. The reversal of 644377446 is 644773446.

644377446 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644377441) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 136221 + ... + 140871.

It is an arithmetic number, because the mean of its divisors is an integer number (29935620).

Almost surely, 2^644377446 is an apocalyptic number.

644377446 is an abundant number, since it is smaller than the sum of its proper divisors (792532314).

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

644377446 is a wasteful number, since it uses less digits than its factorization.

644377446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4881 (or 4878 counting only the distinct ones).

The product of its digits is 1354752, while the sum is 45.

The square root of 644377446 is about 25384.5907195684. The cubic root of 644377446 is about 863.7341887429.

The spelling of 644377446 in words is "six hundred forty-four million, three hundred seventy-seven thousand, four hundred forty-six".