13220312121 has 24 divisors (see below), whose sum is σ = 19696402440. Its totient is φ = 8538483456.

The previous prime is 13220312033. The next prime is 13220312129. The reversal of 13220312121 is 12121302231.

13220312121 is a `hidden beast` number, since 13 + 220 + 312 + 121 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1954612521 + 11265699600 = 44211^2 + 106140^2 .

It is not a de Polignac number, because 13220312121 - 2⁹ = 13220311609 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 13220312094 and 13220312103.

It is not an unprimeable number, because it can be changed into a prime (13220312129) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7606 + ... + 162783.

It is an arithmetic number, because the mean of its divisors is an integer number (820683435).

Almost surely, 2^13220312121 is an apocalyptic number.

It is an amenable number.

13220312121 is a deficient number, since it is larger than the sum of its proper divisors (6476090319).

13220312121 is a wasteful number, since it uses less digits than its factorization.

13220312121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170665 (or 170662 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 13220312121 its reverse (12121302231), we get a palindrome (25341614352).

The spelling of 13220312121 in words is "thirteen billion, two hundred twenty million, three hundred twelve thousand, one hundred twenty-one".