18131213668049 has 2 divisors, whose sum is σ = 18131213668050. Its totient is φ = 18131213668048.

The previous prime is 18131213667989. The next prime is 18131213668079. The reversal of 18131213668049 is 94086631213181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17549606100625 + 581607567424 = 4189225^2 + 762632^2 .

It is a cyclic number.

It is not a de Polignac number, because 18131213668049 - 2²⁸ = 18130945232593 is a prime.

It is not a weakly prime, because it can be changed into another prime (18131213668079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9065606834024 + 9065606834025.

It is an arithmetic number, because the mean of its divisors is an integer number (9065606834025).

Almost surely, 2^{18131213668049} is an apocalyptic number.

It is an amenable number.

18131213668049 is a deficient number, since it is larger than the sum of its proper divisors (1).

18131213668049 is an equidigital number, since it uses as much as digits as its factorization.

18131213668049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1492992, while the sum is 53.

The spelling of 18131213668049 in words is "eighteen trillion, one hundred thirty-one billion, two hundred thirteen million, six hundred sixty-eight thousand, forty-nine".