131566818586564 has 9 divisors (see below), whose sum is σ = 230241972672397. Its totient is φ = 65783397823024.

The previous prime is 131566818586561. The next prime is 131566818586633. The reversal of 131566818586564 is 465685818665131.

The square root of 131566818586564 is 11470258.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 85234292346564 + 46332526240000 = 9232242^2 + 6806800^2 .

It is a super-2 number, since 2×131566818586564² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (131566818586561) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 20072952 + ... + 25808080.

Almost surely, 2^{131566818586564} is an apocalyptic number.

131566818586564 is the 11470258-th square number.

It is an amenable number.

131566818586564 is a deficient number, since it is larger than the sum of its proper divisors (98675154085833).

131566818586564 is an frugal number, since it uses more digits than its factorization.

131566818586564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11470262 (or 5735131 counting only the distinct ones).

The product of its digits is 995328000, while the sum is 73.

The spelling of 131566818586564 in words is "one hundred thirty-one trillion, five hundred sixty-six billion, eight hundred eighteen million, five hundred eighty-six thousand, five hundred sixty-four".