79668139 has 2 divisors, whose sum is σ = 79668140. Its totient is φ = 79668138.

The previous prime is 79668119. The next prime is 79668151. The reversal of 79668139 is 93186697.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 79668139 - 2⁵ = 79668107 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 79668092 and 79668101.

It is not a weakly prime, because it can be changed into another prime (79668119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39834069 + 39834070.

It is an arithmetic number, because the mean of its divisors is an integer number (39834070).

Almost surely, 2^79668139 is an apocalyptic number.

79668139 is a deficient number, since it is larger than the sum of its proper divisors (1).

79668139 is an equidigital number, since it uses as much as digits as its factorization.

79668139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 489888, while the sum is 49.

The square root of 79668139 is about 8925.7010368934. The cubic root of 79668139 is about 430.2903015338.

The spelling of 79668139 in words is "seventy-nine million, six hundred sixty-eight thousand, one hundred thirty-nine".