664583438728 has 16 divisors (see below), whose sum is σ = 1359375215760. Its totient is φ = 302083381200.

The previous prime is 664583438713. The next prime is 664583438759. The reversal of 664583438728 is 827834385466.

It is a happy number.

It is a super-2 number, since 2×664583438728² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 664583438728.

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, 3776042178 + ... + 3776042353.

It is an arithmetic number, because the mean of its divisors is an integer number (84960950985).

Almost surely, 2^664583438728 is an apocalyptic number.

It is an amenable number.

664583438728 is an abundant number, since it is smaller than the sum of its proper divisors (694791777032).

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

664583438728 is a wasteful number, since it uses less digits than its factorization.

664583438728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7552084548 (or 7552084544 counting only the distinct ones).

The product of its digits is 185794560, while the sum is 64.

The spelling of 664583438728 in words is "six hundred sixty-four billion, five hundred eighty-three million, four hundred thirty-eight thousand, seven hundred twenty-eight".