79818131 has 2 divisors, whose sum is σ = 79818132. Its totient is φ = 79818130.

The previous prime is 79818061. The next prime is 79818157. The reversal of 79818131 is 13181897.

It is a strong prime.

It is an emirp because it is prime and its reverse (13181897) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 79818131 - 2²⁶ = 12709267 is a prime.

It is a super-2 number, since 2×79818131² = 12741868072666322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (79818161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39909065 + 39909066.

It is an arithmetic number, because the mean of its divisors is an integer number (39909066).

Almost surely, 2^79818131 is an apocalyptic number.

79818131 is a deficient number, since it is larger than the sum of its proper divisors (1).

79818131 is an equidigital number, since it uses as much as digits as its factorization.

79818131 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12096, while the sum is 38.

The square root of 79818131 is about 8934.0993390492. The cubic root of 79818131 is about 430.5601695245.

The spelling of 79818131 in words is "seventy-nine million, eight hundred eighteen thousand, one hundred thirty-one".