79897865 has 4 divisors (see below), whose sum is σ = 95877444. Its totient is φ = 63918288.

The previous prime is 79897849. The next prime is 79897891. The reversal of 79897865 is 56879897.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56879897 = 23 ⋅2473039.

It can be written as a sum of positive squares in 2 ways, for example, as 49603849 + 30294016 = 7043^2 + 5504^2 .

It is a cyclic number.

It is not a de Polignac number, because 79897865 - 2⁴ = 79897849 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7989782 + ... + 7989791.

It is an arithmetic number, because the mean of its divisors is an integer number (23969361).

Almost surely, 2^79897865 is an apocalyptic number.

It is an amenable number.

79897865 is a deficient number, since it is larger than the sum of its proper divisors (15979579).

79897865 is a wasteful number, since it uses less digits than its factorization.

79897865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15979578.

The product of its digits is 7620480, while the sum is 59.

The square root of 79897865 is about 8938.5605664447. The cubic root of 79897865 is about 430.7034905933.

The spelling of 79897865 in words is "seventy-nine million, eight hundred ninety-seven thousand, eight hundred sixty-five".