644404062644304 has 160 divisors (see below), whose sum is σ = 1709901682621440. Its totient is φ = 209008964376576.

The previous prime is 644404062644267. The next prime is 644404062644327. The reversal of 644404062644304 is 403446260404446.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1170072552 + ... + 1170623160.

It is an arithmetic number, because the mean of its divisors is an integer number (10686885516384).

Almost surely, 2^{644404062644304} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 644404062644304, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (854950841310720).

644404062644304 is an abundant number, since it is smaller than the sum of its proper divisors (1065497619977136).

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

644404062644304 is a wasteful number, since it uses less digits than its factorization.

644404062644304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 552817 (or 552811 counting only the distinct ones).

The product of its (nonzero) digits is 21233664, while the sum is 51.

The spelling of 644404062644304 in words is "six hundred forty-four trillion, four hundred four billion, sixty-two million, six hundred forty-four thousand, three hundred four".