644149177724 has 48 divisors (see below), whose sum is σ = 1274250895680. Its totient is φ = 284373460800.

The previous prime is 644149177703. The next prime is 644149177829. The reversal of 644149177724 is 427771941446.

It is a self number, because there is not a number n which added to its sum of digits gives 644149177724.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1391327 + ... + 1795574.

It is an arithmetic number, because the mean of its divisors is an integer number (26546893660).

Almost surely, 2^644149177724 is an apocalyptic number.

It is an amenable number.

644149177724 is a deficient number, since it is larger than the sum of its proper divisors (630101717956).

644149177724 is a wasteful number, since it uses less digits than its factorization.

644149177724 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3186967 (or 3186939 counting only the distinct ones).

The product of its digits is 9483264, while the sum is 56.

The spelling of 644149177724 in words is "six hundred forty-four billion, one hundred forty-nine million, one hundred seventy-seven thousand, seven hundred twenty-four".