13122031221 has 24 divisors (see below), whose sum is σ = 20468972160. Its totient is φ = 8052577056.

The previous prime is 13122031193. The next prime is 13122031253. The reversal of 13122031221 is 12213022131.

13122031221 is a `hidden beast` number, since 1 + 312 + 20 + 312 + 21 = 666.

It is not a de Polignac number, because 13122031221 - 2²⁵ = 13088476789 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 13122031194 and 13122031203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13122041221) 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, 114201 + ... + 198206.

It is an arithmetic number, because the mean of its divisors is an integer number (852873840).

Almost surely, 2^13122031221 is an apocalyptic number.

It is an amenable number.

13122031221 is a deficient number, since it is larger than the sum of its proper divisors (7346940939).

13122031221 is a wasteful number, since it uses less digits than its factorization.

13122031221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 312785 (or 312782 counting only the distinct ones).

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

Adding to 13122031221 its reverse (12213022131), we get a palindrome (25335053352).

The spelling of 13122031221 in words is "thirteen billion, one hundred twenty-two million, thirty-one thousand, two hundred twenty-one".