79812921 has 8 divisors (see below), whose sum is σ = 111044160. Its totient is φ = 50895152.

The previous prime is 79812913. The next prime is 79812923. The reversal of 79812921 is 12921897.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 79812921 - 2³ = 79812913 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 79812921.

It is not an unprimeable number, because it can be changed into a prime (79812923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 578286 + ... + 578423.

It is an arithmetic number, because the mean of its divisors is an integer number (13880520).

Almost surely, 2^79812921 is an apocalyptic number.

It is an amenable number.

79812921 is a deficient number, since it is larger than the sum of its proper divisors (31231239).

79812921 is a wasteful number, since it uses less digits than its factorization.

79812921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1156735.

The product of its digits is 18144, while the sum is 39.

The square root of 79812921 is about 8933.8077548154. The cubic root of 79812921 is about 430.5508012801.

The spelling of 79812921 in words is "seventy-nine million, eight hundred twelve thousand, nine hundred twenty-one".