79981808 has 20 divisors (see below), whose sum is σ = 156708720. Its totient is φ = 39540864.

The previous prime is 79981801. The next prime is 79981813. The reversal of 79981808 is 80818997.

It is a happy number.

It is a super-2 number, since 2×79981808² = 12794179221897728, which contains 22 as substring.

It is a Smith number, since the sum of its digits (50) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79981801) 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, 26660 + ... + 29507.

It is an arithmetic number, because the mean of its divisors is an integer number (7835436).

Almost surely, 2^79981808 is an apocalyptic number.

It is an amenable number.

79981808 is a deficient number, since it is larger than the sum of its proper divisors (76726912).

79981808 is a wasteful number, since it uses less digits than its factorization.

79981808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56264 (or 56258 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 50.

The square root of 79981808 is about 8943.2548884620. The cubic root of 79981808 is about 430.8542743004.

The spelling of 79981808 in words is "seventy-nine million, nine hundred eighty-one thousand, eight hundred eight".