79981109 has 12 divisors (see below), whose sum is σ = 87435936. Its totient is φ = 73122192.

The previous prime is 79981103. The next prime is 79981117. The reversal of 79981109 is 90118997.

It is not a de Polignac number, because 79981109 - 2²⁴ = 63203893 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 79981109.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79981103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15872 + ... + 20294.

It is an arithmetic number, because the mean of its divisors is an integer number (7286328).

Almost surely, 2^79981109 is an apocalyptic number.

It is an amenable number.

79981109 is a deficient number, since it is larger than the sum of its proper divisors (7454827).

79981109 is a wasteful number, since it uses less digits than its factorization.

79981109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4556 (or 4543 counting only the distinct ones).

The product of its (nonzero) digits is 40824, while the sum is 44.

The square root of 79981109 is about 8943.2158086451. The cubic root of 79981109 is about 430.8530191483.

The spelling of 79981109 in words is "seventy-nine million, nine hundred eighty-one thousand, one hundred nine".