79739991 has 16 divisors (see below), whose sum is σ = 118988800. Its totient is φ = 52775064.

The previous prime is 79739987. The next prime is 79739999. The reversal of 79739991 is 19993797.

It is not a de Polignac number, because 79739991 - 2² = 79739987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79739999) 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 in 15 ways as a sum of consecutive naturals, for example, 6871 + ... + 14376.

It is an arithmetic number, because the mean of its divisors is an integer number (7436800).

Almost surely, 2^79739991 is an apocalyptic number.

79739991 is a deficient number, since it is larger than the sum of its proper divisors (39248809).

79739991 is a wasteful number, since it uses less digits than its factorization.

79739991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21395 (or 21389 counting only the distinct ones).

The product of its digits is 964467, while the sum is 54.

The square root of 79739991 is about 8929.7251357475. The cubic root of 79739991 is about 430.4196210214.

The spelling of 79739991 in words is "seventy-nine million, seven hundred thirty-nine thousand, nine hundred ninety-one".