664516699956 has 60 divisors (see below), whose sum is σ = 1797080628420. Its totient is φ = 213867440640.

The previous prime is 664516699943. The next prime is 664516699997. The reversal of 664516699956 is 659996615466.

It is a happy number.

664516699956 is a `hidden beast` number, since 66 + 451 + 6 + 69 + 9 + 9 + 56 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 463875415056 + 200641284900 = 681084^2 + 447930^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 35352285 + ... + 35371076.

It is an arithmetic number, because the mean of its divisors is an integer number (29951343807).

Almost surely, 2^664516699956 is an apocalyptic number.

It is an amenable number.

664516699956 is an abundant number, since it is smaller than the sum of its proper divisors (1132563928464).

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

664516699956 is a wasteful number, since it uses less digits than its factorization.

664516699956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70723406 (or 70723395 counting only the distinct ones).

The product of its digits is 566870400, while the sum is 72.

The spelling of 664516699956 in words is "six hundred sixty-four billion, five hundred sixteen million, six hundred ninety-nine thousand, nine hundred fifty-six".