79521121 has 4 divisors (see below), whose sum is σ = 84198852. Its totient is φ = 74843392.

The previous prime is 79521119. The next prime is 79521157. The reversal of 79521121 is 12112597.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12112597 = 7 ⋅1730371.

It can be written as a sum of positive squares in 2 ways, for example, as 68558400 + 10962721 = 8280^2 + 3311^2 .

It is a cyclic number.

It is not a de Polignac number, because 79521121 - 2¹ = 79521119 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 79521121.

It is not an unprimeable number, because it can be changed into a prime (79521721) 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, 2338840 + ... + 2338873.

It is an arithmetic number, because the mean of its divisors is an integer number (21049713).

Almost surely, 2^79521121 is an apocalyptic number.

It is an amenable number.

79521121 is a deficient number, since it is larger than the sum of its proper divisors (4677731).

79521121 is a wasteful number, since it uses less digits than its factorization.

79521121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4677730.

The product of its digits is 1260, while the sum is 28.

The square root of 79521121 is about 8917.4615782744. The cubic root of 79521121 is about 430.0254554968.

The spelling of 79521121 in words is "seventy-nine million, five hundred twenty-one thousand, one hundred twenty-one".