13111111231 has 4 divisors (see below), whose sum is σ = 13112107632. Its totient is φ = 13110114832.

The previous prime is 13111111213. The next prime is 13111111249. The reversal of 13111111231 is 13211111131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13211111131 = 2311 ⋅5716621.

It is an interprime number because it is at equal distance from previous prime (13111111213) and next prime (13111111249).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13111111231 is a prime.

It is a super-2 number, since 2×13111111231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13111111631) 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, 478195 + ... + 504868.

It is an arithmetic number, because the mean of its divisors is an integer number (3278026908).

Almost surely, 2^13111111231 is an apocalyptic number.

13111111231 is a deficient number, since it is larger than the sum of its proper divisors (996401).

13111111231 is an equidigital number, since it uses as much as digits as its factorization.

13111111231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 996400.

The product of its digits is 18, while the sum is 16.

Adding to 13111111231 its reverse (13211111131), we get a palindrome (26322222362).

The spelling of 13111111231 in words is "thirteen billion, one hundred eleven million, one hundred eleven thousand, two hundred thirty-one".