79781812 has 12 divisors (see below), whose sum is σ = 152310816. Its totient is φ = 36264440.

The previous prime is 79781809. The next prime is 79781827. The reversal of 79781812 is 21818797.

It is a happy number.

It is a congruent 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, 906568 + ... + 906655.

It is an arithmetic number, because the mean of its divisors is an integer number (12692568).

Almost surely, 2^79781812 is an apocalyptic number.

It is an amenable number.

79781812 is a deficient number, since it is larger than the sum of its proper divisors (72529004).

79781812 is a wasteful number, since it uses less digits than its factorization.

79781812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1813238 (or 1813236 counting only the distinct ones).

The product of its digits is 56448, while the sum is 43.

The square root of 79781812 is about 8932.0665022155. The cubic root of 79781812 is about 430.4948548439.

The spelling of 79781812 in words is "seventy-nine million, seven hundred eighty-one thousand, eight hundred twelve".