79878121 has 8 divisors (see below), whose sum is σ = 85597344. Its totient is φ = 74272320.

The previous prime is 79878107. The next prime is 79878131. The reversal of 79878121 is 12187897.

It is a happy number.

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

It is not a de Polignac number, because 79878121 - 2²⁵ = 46323689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79878101) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26895 + ... + 29716.

It is an arithmetic number, because the mean of its divisors is an integer number (10699668).

Almost surely, 2^79878121 is an apocalyptic number.

It is an amenable number.

79878121 is a deficient number, since it is larger than the sum of its proper divisors (5719223).

79878121 is a wasteful number, since it uses less digits than its factorization.

79878121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56711.

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

The square root of 79878121 is about 8937.4560698221. The cubic root of 79878121 is about 430.6680098359.

The spelling of 79878121 in words is "seventy-nine million, eight hundred seventy-eight thousand, one hundred twenty-one".