13121223131 has 4 divisors (see below), whose sum is σ = 13141134600. Its totient is φ = 13101311664.

The previous prime is 13121223127. The next prime is 13121223133. The reversal of 13121223131 is 13132212131.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 13121223131 - 2² = 13121223127 is a prime.

It is a super-2 number, since 2×13121223131² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13121223133) 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, 9954746 + ... + 9956063.

It is an arithmetic number, because the mean of its divisors is an integer number (3285283650).

Almost surely, 2^13121223131 is an apocalyptic number.

13121223131 is a deficient number, since it is larger than the sum of its proper divisors (19911469).

13121223131 is an equidigital number, since it uses as much as digits as its factorization.

13121223131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19911468.

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

Adding to 13121223131 its reverse (13132212131), we get a palindrome (26253435262).

The spelling of 13121223131 in words is "thirteen billion, one hundred twenty-one million, two hundred twenty-three thousand, one hundred thirty-one".