18517723264693 has 2 divisors, whose sum is σ = 18517723264694. Its totient is φ = 18517723264692.

The previous prime is 18517723264619. The next prime is 18517723264757. The reversal of 18517723264693 is 39646232771581.

It is an a-pointer prime, because the next prime (18517723264757) can be obtained adding 18517723264693 to its sum of digits (64).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18434803454929 + 82919809764 = 4293577^2 + 287958^2 .

It is an emirp because it is prime and its reverse (39646232771581) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18517723264693 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18517723264093) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9258861632346 + 9258861632347.

It is an arithmetic number, because the mean of its divisors is an integer number (9258861632347).

Almost surely, 2^{18517723264693} is an apocalyptic number.

It is an amenable number.

18517723264693 is a deficient number, since it is larger than the sum of its proper divisors (1).

18517723264693 is an equidigital number, since it uses as much as digits as its factorization.

18517723264693 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 91445760, while the sum is 64.

The spelling of 18517723264693 in words is "eighteen trillion, five hundred seventeen billion, seven hundred twenty-three million, two hundred sixty-four thousand, six hundred ninety-three".