644785587446 has 96 divisors (see below), whose sum is σ = 1350750816000. Its totient is φ = 223894419840.

The previous prime is 644785587421. The next prime is 644785587487.

644785587446 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 327605 + ... + 1181903.

It is an arithmetic number, because the mean of its divisors is an integer number (14070321000).

Almost surely, 2^644785587446 is an apocalyptic number.

644785587446 is an abundant number, since it is smaller than the sum of its proper divisors (705965228554).

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

644785587446 is a wasteful number, since it uses less digits than its factorization.

644785587446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 854374 (or 854361 counting only the distinct ones).

The product of its digits is 722534400, while the sum is 68.

The spelling of 644785587446 in words is "six hundred forty-four billion, seven hundred eighty-five million, five hundred eighty-seven thousand, four hundred forty-six".