18242138491 has 2 divisors, whose sum is σ = 18242138492. Its totient is φ = 18242138490.

The previous prime is 18242138471. The next prime is 18242138501. The reversal of 18242138491 is 19483124281.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18242138491 - 2⁵ = 18242138459 is a prime.

It is not a weakly prime, because it can be changed into another prime (18242138471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9121069245 + 9121069246.

It is an arithmetic number, because the mean of its divisors is an integer number (9121069246).

Almost surely, 2^18242138491 is an apocalyptic number.

18242138491 is a deficient number, since it is larger than the sum of its proper divisors (1).

18242138491 is an equidigital number, since it uses as much as digits as its factorization.

18242138491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 110592, while the sum is 43.

The spelling of 18242138491 in words is "eighteen billion, two hundred forty-two million, one hundred thirty-eight thousand, four hundred ninety-one".