79899899 has 4 divisors (see below), whose sum is σ = 79917840. Its totient is φ = 79881960.

The previous prime is 79899863. The next prime is 79899929. The reversal of 79899899 is 99899897.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 99899897 = 313 ⋅319169.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-79899899 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79899299) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3362 + ... + 13080.

It is an arithmetic number, because the mean of its divisors is an integer number (19979460).

Almost surely, 2^79899899 is an apocalyptic number.

79899899 is a deficient number, since it is larger than the sum of its proper divisors (17941).

79899899 is an equidigital number, since it uses as much as digits as its factorization.

79899899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17940.

The product of its digits is 26453952, while the sum is 68.

The square root of 79899899 is about 8938.6743424291. The cubic root of 79899899 is about 430.7071454405.

The spelling of 79899899 in words is "seventy-nine million, eight hundred ninety-nine thousand, eight hundred ninety-nine".