18686566815973 has 16 divisors (see below), whose sum is σ = 21360880834560. Its totient is φ = 16013454433200.

The previous prime is 18686566815919. The next prime is 18686566816033. The reversal of 18686566815973 is 37951866568681.

It is not a de Polignac number, because 18686566815973 - 2²⁵ = 18686533261541 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18686566815893 and 18686566815902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18686566815673) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1039808878 + ... + 1039826848.

It is an arithmetic number, because the mean of its divisors is an integer number (1335055052160).

Almost surely, 2^{18686566815973} is an apocalyptic number.

It is an amenable number.

18686566815973 is a deficient number, since it is larger than the sum of its proper divisors (2674314018587).

18686566815973 is a wasteful number, since it uses less digits than its factorization.

18686566815973 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43128.

The product of its digits is 3135283200, while the sum is 79.

The spelling of 18686566815973 in words is "eighteen trillion, six hundred eighty-six billion, five hundred sixty-six million, eight hundred fifteen thousand, nine hundred seventy-three".