79516891 has 4 divisors (see below), whose sum is σ = 82081984. Its totient is φ = 76951800.

The previous prime is 79516841. The next prime is 79516901. The reversal of 79516891 is 19861597.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19861597 = 7 ⋅2837371.

It is a cyclic number.

It is not a de Polignac number, because 79516891 - 2²¹ = 77419739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79516831) 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, 1282500 + ... + 1282561.

It is an arithmetic number, because the mean of its divisors is an integer number (20520496).

Almost surely, 2^79516891 is an apocalyptic number.

79516891 is a deficient number, since it is larger than the sum of its proper divisors (2565093).

79516891 is a wasteful number, since it uses less digits than its factorization.

79516891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2565092.

The product of its digits is 136080, while the sum is 46.

The square root of 79516891 is about 8917.2244000025. The cubic root of 79516891 is about 430.0178305208.

The spelling of 79516891 in words is "seventy-nine million, five hundred sixteen thousand, eight hundred ninety-one".