1231113131 has 4 divisors (see below), whose sum is σ = 1239970200. Its totient is φ = 1222256064.

The previous prime is 1231113119. The next prime is 1231113209. The reversal of 1231113131 is 1313111321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1313111321 = 4373 ⋅300277.

It is a cyclic number.

It is not a de Polignac number, because 1231113131 - 2²² = 1226918827 is a prime.

It is a super-2 number, since 2×1231113131² = 3031279082641246322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1231112131) 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, 4428326 + ... + 4428603.

It is an arithmetic number, because the mean of its divisors is an integer number (309992550).

Almost surely, 2^1231113131 is an apocalyptic number.

1231113131 is a deficient number, since it is larger than the sum of its proper divisors (8857069).

1231113131 is an equidigital number, since it uses as much as digits as its factorization.

1231113131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8857068.

The product of its digits is 54, while the sum is 17.

The square root of 1231113131 is about 35087.2217623453. The cubic root of 1231113131 is about 1071.7643848384.

Adding to 1231113131 its reverse (1313111321), we get a palindrome (2544224452).

The spelling of 1231113131 in words is "one billion, two hundred thirty-one million, one hundred thirteen thousand, one hundred thirty-one".