79980091 has 2 divisors, whose sum is σ = 79980092. Its totient is φ = 79980090.

The previous prime is 79980083. The next prime is 79980113. The reversal of 79980091 is 19008997.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 79980091 - 2³ = 79980083 is a prime.

It is not a weakly prime, because it can be changed into another prime (79980191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39990045 + 39990046.

It is an arithmetic number, because the mean of its divisors is an integer number (39990046).

Almost surely, 2^79980091 is an apocalyptic number.

79980091 is a deficient number, since it is larger than the sum of its proper divisors (1).

79980091 is an equidigital number, since it uses as much as digits as its factorization.

79980091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 43.

The square root of 79980091 is about 8943.1588938138. The cubic root of 79980091 is about 430.8511911740.

The spelling of 79980091 in words is "seventy-nine million, nine hundred eighty thousand, ninety-one".