79686642 has 24 divisors (see below), whose sum is σ = 185394096. Its totient is φ = 22767528.

The previous prime is 79686623. The next prime is 79686643. The reversal of 79686642 is 24668697.

It is a junction number, because it is equal to n+sod(n) for n = 79686591 and 79686600.

It is not an unprimeable number, because it can be changed into a prime (79686643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 135228 + ... + 135815.

It is an arithmetic number, because the mean of its divisors is an integer number (7724754).

Almost surely, 2^79686642 is an apocalyptic number.

79686642 is an abundant number, since it is smaller than the sum of its proper divisors (105707454).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

79686642 is a wasteful number, since it uses less digits than its factorization.

79686642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 271062 (or 271055 counting only the distinct ones).

The product of its digits is 870912, while the sum is 48.

The square root of 79686642 is about 8926.7374779367. The cubic root of 79686642 is about 430.3236107306.

The spelling of 79686642 in words is "seventy-nine million, six hundred eighty-six thousand, six hundred forty-two".