644056366624 has 24 divisors (see below), whose sum is σ = 1383257424528. Its totient is φ = 292752893760.

The previous prime is 644056366589. The next prime is 644056366631. The reversal of 644056366624 is 426663650446.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 914852442 + ... + 914853145.

It is an arithmetic number, because the mean of its divisors is an integer number (57635726022).

Almost surely, 2^644056366624 is an apocalyptic number.

It is an amenable number.

644056366624 is an abundant number, since it is smaller than the sum of its proper divisors (739201057904).

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

644056366624 is a wasteful number, since it uses less digits than its factorization.

644056366624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1829705608 (or 1829705600 counting only the distinct ones).

The product of its (nonzero) digits is 14929920, while the sum is 52.

The spelling of 644056366624 in words is "six hundred forty-four billion, fifty-six million, three hundred sixty-six thousand, six hundred twenty-four".