13120123221 has 12 divisors (see below), whose sum is σ = 18983255148. Its totient is φ = 8731995264.

The previous prime is 13120123217. The next prime is 13120123223. The reversal of 13120123221 is 12232102131.

It can be written as a sum of positive squares in 2 ways, for example, as 5039012196 + 8081111025 = 70986^2 + 89895^2 .

It is not a de Polignac number, because 13120123221 - 2² = 13120123217 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 13120123194 and 13120123203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13120123223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1223830 + ... + 1234503.

It is an arithmetic number, because the mean of its divisors is an integer number (1581937929).

Almost surely, 2^13120123221 is an apocalyptic number.

It is an amenable number.

13120123221 is a deficient number, since it is larger than the sum of its proper divisors (5863131927).

13120123221 is a wasteful number, since it uses less digits than its factorization.

13120123221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2458932 (or 2458929 counting only the distinct ones).

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

Adding to 13120123221 its reverse (12232102131), we get a palindrome (25352225352).

The spelling of 13120123221 in words is "thirteen billion, one hundred twenty million, one hundred twenty-three thousand, two hundred twenty-one".