79996991 has 2 divisors, whose sum is σ = 79996992. Its totient is φ = 79996990.

The previous prime is 79996933. The next prime is 79996999. The reversal of 79996991 is 19969997.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 79996991 - 2⁶ = 79996927 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 79996991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79996999) 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, 39998495 + 39998496.

It is an arithmetic number, because the mean of its divisors is an integer number (39998496).

Almost surely, 2^79996991 is an apocalyptic number.

79996991 is a deficient number, since it is larger than the sum of its proper divisors (1).

79996991 is an equidigital number, since it uses as much as digits as its factorization.

79996991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2480058, while the sum is 59.

The square root of 79996991 is about 8944.1037002038. The cubic root of 79996991 is about 430.8815356937.

The spelling of 79996991 in words is "seventy-nine million, nine hundred ninety-six thousand, nine hundred ninety-one".