81052766590761 has 81 divisors (see below), whose sum is σ = 136611008272791. Its totient is φ = 46173368231424.

The previous prime is 81052766590703. The next prime is 81052766590799. The reversal of 81052766590761 is 16709566725018.

The square root of 81052766590761 is 9002931.

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

81052766590761 is a `hidden beast` number, since 8 + 10 + 5 + 27 + 6 + 6 + 590 + 7 + 6 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 80491849475625 + 560917115136 = 8971725^2 + 748944^2 .

It is not a de Polignac number, because 81052766590761 - 2³⁵ = 81018406852393 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81052766598761) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 109088514556 + ... + 109088515298.

Almost surely, 2^{81052766590761} is an apocalyptic number.

81052766590761 is the 9002931-st square number.

81052766590761 is the 4501466-th centered octagonal number.

It is an amenable number.

81052766590761 is a deficient number, since it is larger than the sum of its proper divisors (55558241682030).

81052766590761 is an frugal number, since it uses more digits than its factorization.

81052766590761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2660 (or 1330 counting only the distinct ones).

The product of its (nonzero) digits is 38102400, while the sum is 63.

The spelling of 81052766590761 in words is "eighty-one trillion, fifty-two billion, seven hundred sixty-six million, five hundred ninety thousand, seven hundred sixty-one".