644760492612 has 12 divisors (see below), whose sum is σ = 1504441149456. Its totient is φ = 214920164200.

The previous prime is 644760492599. The next prime is 644760492641. The reversal of 644760492612 is 216294067446.

It is a tau number, because it is divible by the number of its divisors (12).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26865020514 + ... + 26865020537.

It is an arithmetic number, because the mean of its divisors is an integer number (125370095788).

Almost surely, 2^644760492612 is an apocalyptic number.

It is an amenable number.

644760492612 is an abundant number, since it is smaller than the sum of its proper divisors (859680656844).

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

644760492612 is a wasteful number, since it uses less digits than its factorization.

644760492612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53730041058 (or 53730041056 counting only the distinct ones).

The product of its (nonzero) digits is 3483648, while the sum is 51.

The spelling of 644760492612 in words is "six hundred forty-four billion, seven hundred sixty million, four hundred ninety-two thousand, six hundred twelve".