81311336568684 has 72 divisors (see below), whose sum is σ = 206103180563280. Its totient is φ = 27029141903232.

The previous prime is 81311336568677. The next prime is 81311336568731. The reversal of 81311336568684 is 48686563311318.

81311336568684 is a `hidden beast` number, since 8 + 1 + 3 + 1 + 1 + 3 + 3 + 6 + 568 + 68 + 4 = 666.

It is a super-2 number, since 2×81311336568684² (a number of 29 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 76169847 + ... + 77229969.

It is an arithmetic number, because the mean of its divisors is an integer number (2862544174490).

Almost surely, 2^{81311336568684} is an apocalyptic number.

It is an amenable number.

81311336568684 is an abundant number, since it is smaller than the sum of its proper divisors (124791843994596).

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

81311336568684 is a wasteful number, since it uses less digits than its factorization.

81311336568684 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1065999 (or 1065994 counting only the distinct ones).

The product of its digits is 59719680, while the sum is 63.

The spelling of 81311336568684 in words is "eighty-one trillion, three hundred eleven billion, three hundred thirty-six million, five hundred sixty-eight thousand, six hundred eighty-four".