131231311 has 4 divisors (see below), whose sum is σ = 131536224. Its totient is φ = 130926400.

The previous prime is 131231299. The next prime is 131231323. The reversal of 131231311 is 113132131.

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

It is an interprime number because it is at equal distance from previous prime (131231299) and next prime (131231323).

It is a cyclic number.

It is not a de Polignac number, because 131231311 - 2⁷ = 131231183 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131231371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 151810 + ... + 152671.

It is an arithmetic number, because the mean of its divisors is an integer number (32884056).

Almost surely, 2^131231311 is an apocalyptic number.

131231311 is a deficient number, since it is larger than the sum of its proper divisors (304913).

131231311 is an equidigital number, since it uses as much as digits as its factorization.

131231311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304912.

The product of its digits is 54, while the sum is 16.

The square root of 131231311 is about 11455.6235535217. The cubic root of 131231311 is about 508.1740560796.

Adding to 131231311 its reverse (113132131), we get a palindrome (244363442).

It can be divided in two parts, 1312 and 31311, that added together give a palindrome (32623).

The spelling of 131231311 in words is "one hundred thirty-one million, two hundred thirty-one thousand, three hundred eleven".