79947864 has 64 divisors (see below), whose sum is σ = 222912000. Its totient is φ = 26549280.

The previous prime is 79947851. The next prime is 79947869. The reversal of 79947864 is 46874997.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 79947864.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79947869) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 77029 + ... + 78059.

It is an arithmetic number, because the mean of its divisors is an integer number (3483000).

Almost surely, 2^79947864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 79947864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111456000).

79947864 is an abundant number, since it is smaller than the sum of its proper divisors (142964136).

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

79947864 is a wasteful number, since it uses less digits than its factorization.

79947864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1405 (or 1395 counting only the distinct ones).

The product of its digits is 3048192, while the sum is 54.

The square root of 79947864 is about 8941.3569439990. The cubic root of 79947864 is about 430.7933146595.

The spelling of 79947864 in words is "seventy-nine million, nine hundred forty-seven thousand, eight hundred sixty-four".