79876021 has 4 divisors (see below), whose sum is σ = 79950592. Its totient is φ = 79801452.

The previous prime is 79875989. The next prime is 79876037. The reversal of 79876021 is 12067897.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12067897 = 31 ⋅389287.

It is a cyclic number.

It is not a de Polignac number, because 79876021 - 2⁵ = 79875989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79876061) 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, 35655 + ... + 37828.

It is an arithmetic number, because the mean of its divisors is an integer number (19987648).

Almost surely, 2^79876021 is an apocalyptic number.

It is an amenable number.

79876021 is a deficient number, since it is larger than the sum of its proper divisors (74571).

79876021 is a wasteful number, since it uses less digits than its factorization.

79876021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74570.

The product of its (nonzero) digits is 42336, while the sum is 40.

The square root of 79876021 is about 8937.3385859550. The cubic root of 79876021 is about 430.6642357080.

The spelling of 79876021 in words is "seventy-nine million, eight hundred seventy-six thousand, twenty-one".