79128911 has 2 divisors, whose sum is σ = 79128912. Its totient is φ = 79128910.

The previous prime is 79128887. The next prime is 79128913. The reversal of 79128911 is 11982197.

It is a strong prime.

It is an emirp because it is prime and its reverse (11982197) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-79128911 is a prime.

It is a super-2 number, since 2×79128911² = 12522769112091842, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 79128913, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79128913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39564455 + 39564456.

It is an arithmetic number, because the mean of its divisors is an integer number (39564456).

Almost surely, 2^79128911 is an apocalyptic number.

79128911 is a deficient number, since it is larger than the sum of its proper divisors (1).

79128911 is an equidigital number, since it uses as much as digits as its factorization.

79128911 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9072, while the sum is 38.

The square root of 79128911 is about 8895.4432716982. The cubic root of 79128911 is about 429.3173068107.

The spelling of 79128911 in words is "seventy-nine million, one hundred twenty-eight thousand, nine hundred eleven".