18318363634121 has 2 divisors, whose sum is σ = 18318363634122. Its totient is φ = 18318363634120.

The previous prime is 18318363634093. The next prime is 18318363634177. The reversal of 18318363634121 is 12143636381381.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17387765778496 + 930597855625 = 4169864^2 + 964675^2 .

It is a cyclic number.

It is not a de Polignac number, because 18318363634121 - 2⁶ = 18318363634057 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18318363634121.

It is not a weakly prime, because it can be changed into another prime (18318363634421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9159181817060 + 9159181817061.

It is an arithmetic number, because the mean of its divisors is an integer number (9159181817061).

Almost surely, 2^{18318363634121} is an apocalyptic number.

It is an amenable number.

18318363634121 is a deficient number, since it is larger than the sum of its proper divisors (1).

18318363634121 is an equidigital number, since it uses as much as digits as its factorization.

18318363634121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1492992, while the sum is 50.

The spelling of 18318363634121 in words is "eighteen trillion, three hundred eighteen billion, three hundred sixty-three million, six hundred thirty-four thousand, one hundred twenty-one".