79599991 has 2 divisors, whose sum is σ = 79599992. Its totient is φ = 79599990.

The previous prime is 79599979. The next prime is 79600013. The reversal of 79599991 is 19999597.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 79599991 - 2⁹ = 79599479 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79599931) 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, 39799995 + 39799996.

It is an arithmetic number, because the mean of its divisors is an integer number (39799996).

Almost surely, 2^79599991 is an apocalyptic number.

79599991 is a deficient number, since it is larger than the sum of its proper divisors (1).

79599991 is an equidigital number, since it uses as much as digits as its factorization.

79599991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2066715, while the sum is 58.

The square root of 79599991 is about 8921.8827049004. The cubic root of 79599991 is about 430.1675766533.

The spelling of 79599991 in words is "seventy-nine million, five hundred ninety-nine thousand, nine hundred ninety-one".