111131231 has 2 divisors, whose sum is σ = 111131232. Its totient is φ = 111131230.

The previous prime is 111131213. The next prime is 111131233. The reversal of 111131231 is 132131111.

It is a happy number.

Together with previous prime (111131213) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111131231 is a prime.

It is a super-2 number, since 2×111131231² = 24700301007150722, which contains 22 as substring.

Together with 111131233, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111131233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55565615 + 55565616.

It is an arithmetic number, because the mean of its divisors is an integer number (55565616).

Almost surely, 2^111131231 is an apocalyptic number.

111131231 is a deficient number, since it is larger than the sum of its proper divisors (1).

111131231 is an equidigital number, since it uses as much as digits as its factorization.

111131231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18, while the sum is 14.

The square root of 111131231 is about 10541.8798608218. The cubic root of 111131231 is about 480.7788729189.

Adding to 111131231 its reverse (132131111), we get a palindrome (243262342).

The spelling of 111131231 in words is "one hundred eleven million, one hundred thirty-one thousand, two hundred thirty-one".