79866921 has 8 divisors (see below), whose sum is σ = 107523520. Its totient is φ = 52727472.

The previous prime is 79866883. The next prime is 79866949. The reversal of 79866921 is 12966897.

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

It is a de Polignac number, because none of the positive numbers 2^k-79866921 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (79866961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 128926 + ... + 129543.

It is an arithmetic number, because the mean of its divisors is an integer number (13440440).

Almost surely, 2^79866921 is an apocalyptic number.

It is an amenable number.

79866921 is a deficient number, since it is larger than the sum of its proper divisors (27656599).

79866921 is a wasteful number, since it uses less digits than its factorization.

79866921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 258575.

The product of its digits is 326592, while the sum is 48.

The square root of 79866921 is about 8936.8294713506. The cubic root of 79866921 is about 430.6478803891.

The spelling of 79866921 in words is "seventy-nine million, eight hundred sixty-six thousand, nine hundred twenty-one".