18516356317 has 2 divisors, whose sum is σ = 18516356318. Its totient is φ = 18516356316.

The previous prime is 18516356297. The next prime is 18516356359. The reversal of 18516356317 is 71365361581.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18456309316 + 60047001 = 135854^2 + 7749^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18516356317 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18516356717) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9258178158 + 9258178159.

It is an arithmetic number, because the mean of its divisors is an integer number (9258178159).

Almost surely, 2^18516356317 is an apocalyptic number.

It is an amenable number.

18516356317 is a deficient number, since it is larger than the sum of its proper divisors (1).

18516356317 is an equidigital number, since it uses as much as digits as its factorization.

18516356317 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 453600, while the sum is 46.

The spelling of 18516356317 in words is "eighteen billion, five hundred sixteen million, three hundred fifty-six thousand, three hundred seventeen".