665320320554664 has 128 divisors (see below), whose sum is σ = 1823798577070080. Its totient is φ = 201345282124800.

The previous prime is 665320320554641. The next prime is 665320320554671. The reversal of 665320320554664 is 466455023023566.

It is a super-2 number, since 2×665320320554664² (a number of 30 digits) contains 22 as substring.

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, 80636904 + ... + 88503959.

It is an arithmetic number, because the mean of its divisors is an integer number (14248426383360).

Almost surely, 2^{665320320554664} is an apocalyptic number.

It is an amenable number.

665320320554664 is an abundant number, since it is smaller than the sum of its proper divisors (1158478256515416).

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

665320320554664 is a wasteful number, since it uses less digits than its factorization.

665320320554664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169141231 (or 169141227 counting only the distinct ones).

The product of its (nonzero) digits is 93312000, while the sum is 57.

The spelling of 665320320554664 in words is "six hundred sixty-five trillion, three hundred twenty billion, three hundred twenty million, five hundred fifty-four thousand, six hundred sixty-four".