18681327635717 has 2 divisors, whose sum is σ = 18681327635718. Its totient is φ = 18681327635716.

The previous prime is 18681327635687. The next prime is 18681327635731. The reversal of 18681327635717 is 71753672318681.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18189423188836 + 491904446881 = 4264906^2 + 701359^2 .

It is a cyclic number.

It is not a de Polignac number, because 18681327635717 - 2⁸ = 18681327635461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18681327635017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9340663817858 + 9340663817859.

It is an arithmetic number, because the mean of its divisors is an integer number (9340663817859).

Almost surely, 2^{18681327635717} is an apocalyptic number.

It is an amenable number.

18681327635717 is a deficient number, since it is larger than the sum of its proper divisors (1).

18681327635717 is an equidigital number, since it uses as much as digits as its factorization.

18681327635717 is an evil number, because the sum of its binary digits is even.

The product of its digits is 71124480, while the sum is 65.

The spelling of 18681327635717 in words is "eighteen trillion, six hundred eighty-one billion, three hundred twenty-seven million, six hundred thirty-five thousand, seven hundred seventeen".