644273239390716 has 48 divisors (see below), whose sum is σ = 1618947211675808. Its totient is φ = 198237405542400.

The previous prime is 644273239390663. The next prime is 644273239390727. The reversal of 644273239390716 is 617093932372446.

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, 57312036 + ... + 67625556.

Almost surely, 2^{644273239390716} is an apocalyptic number.

It is an amenable number.

644273239390716 is an abundant number, since it is smaller than the sum of its proper divisors (974673972285092).

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

644273239390716 is a wasteful number, since it uses less digits than its factorization.

644273239390716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10713982 (or 10713980 counting only the distinct ones).

The product of its (nonzero) digits is 246903552, while the sum is 66.

The spelling of 644273239390716 in words is "six hundred forty-four trillion, two hundred seventy-three billion, two hundred thirty-nine million, three hundred ninety thousand, seven hundred sixteen".