665131186885 has 16 divisors (see below), whose sum is σ = 875275932672. Its totient is φ = 481199137600.

The previous prime is 665131186789. The next prime is 665131186897. The reversal of 665131186885 is 588681131566.

It is a happy number.

It is not a de Polignac number, because 665131186885 - 2²⁷ = 664996969157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31647334 + ... + 31668343.

It is an arithmetic number, because the mean of its divisors is an integer number (54704745792).

Almost surely, 2^665131186885 is an apocalyptic number.

It is an amenable number.

665131186885 is a deficient number, since it is larger than the sum of its proper divisors (210144745787).

665131186885 is a wasteful number, since it uses less digits than its factorization.

665131186885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63315884.

The product of its digits is 8294400, while the sum is 58.

The spelling of 665131186885 in words is "six hundred sixty-five billion, one hundred thirty-one million, one hundred eighty-six thousand, eight hundred eighty-five".