18966320918717 has 2 divisors, whose sum is σ = 18966320918718. Its totient is φ = 18966320918716.

The previous prime is 18966320918639. The next prime is 18966320918719. The reversal of 18966320918717 is 71781902366981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11898560426041 + 7067760492676 = 3449429^2 + 2658526^2 .

It is an emirp because it is prime and its reverse (71781902366981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18966320918717 - 2²² = 18966316724413 is a prime.

Together with 18966320918719, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18966320918719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9483160459358 + 9483160459359.

It is an arithmetic number, because the mean of its divisors is an integer number (9483160459359).

Almost surely, 2^{18966320918717} is an apocalyptic number.

It is an amenable number.

18966320918717 is a deficient number, since it is larger than the sum of its proper divisors (1).

18966320918717 is an equidigital number, since it uses as much as digits as its factorization.

18966320918717 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54867456, while the sum is 68.

The spelling of 18966320918717 in words is "eighteen trillion, nine hundred sixty-six billion, three hundred twenty million, nine hundred eighteen thousand, seven hundred seventeen".