18215265413 has 2 divisors, whose sum is σ = 18215265414. Its totient is φ = 18215265412.

The previous prime is 18215265379. The next prime is 18215265421. The reversal of 18215265413 is 31456251281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11249359969 + 6965905444 = 106063^2 + 83462^2 .

It is a cyclic number.

It is not a de Polignac number, because 18215265413 - 2²⁴ = 18198488197 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18215265473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9107632706 + 9107632707.

It is an arithmetic number, because the mean of its divisors is an integer number (9107632707).

Almost surely, 2^18215265413 is an apocalyptic number.

It is an amenable number.

18215265413 is a deficient number, since it is larger than the sum of its proper divisors (1).

18215265413 is an equidigital number, since it uses as much as digits as its factorization.

18215265413 is an evil number, because the sum of its binary digits is even.

The product of its digits is 57600, while the sum is 38.

The spelling of 18215265413 in words is "eighteen billion, two hundred fifteen million, two hundred sixty-five thousand, four hundred thirteen".