13131122321 has 4 divisors (see below), whose sum is σ = 13554706944. Its totient is φ = 12707537700.

The previous prime is 13131122317. The next prime is 13131122327. The reversal of 13131122321 is 12322113131.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12322113131 = 33149 ⋅371719.

It is a cyclic number.

It is not a de Polignac number, because 13131122321 - 2² = 13131122317 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 13131122293 and 13131122302.

It is not an unprimeable number, because it can be changed into a prime (13131122327) 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, 211792265 + ... + 211792326.

It is an arithmetic number, because the mean of its divisors is an integer number (3388676736).

Almost surely, 2^13131122321 is an apocalyptic number.

It is an amenable number.

13131122321 is a deficient number, since it is larger than the sum of its proper divisors (423584623).

13131122321 is an equidigital number, since it uses as much as digits as its factorization.

13131122321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 423584622.

The product of its digits is 216, while the sum is 20.

Adding to 13131122321 its reverse (12322113131), we get a palindrome (25453235452).

The spelling of 13131122321 in words is "thirteen billion, one hundred thirty-one million, one hundred twenty-two thousand, three hundred twenty-one".