131231111111 has 2 divisors, whose sum is σ = 131231111112. Its totient is φ = 131231111110.

The previous prime is 131231111051. The next prime is 131231111129. The reversal of 131231111111 is 111111132131.

It is a happy number.

It is a m-pointer prime, because the next prime (131231111129) can be obtained adding 131231111111 to its product of digits (18).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 131231111111 - 2¹⁸ = 131230848967 is a prime.

131231111111 is a modest number, since divided by 1111111 gives 13123 as remainder.

It is a self number, because there is not a number n which added to its sum of digits gives 131231111111.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131251111111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65615555555 + 65615555556.

It is an arithmetic number, because the mean of its divisors is an integer number (65615555556).

Almost surely, 2^131231111111 is an apocalyptic number.

131231111111 is a deficient number, since it is larger than the sum of its proper divisors (1).

131231111111 is an equidigital number, since it uses as much as digits as its factorization.

131231111111 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18, while the sum is 17.

Adding to 131231111111 its reverse (111111132131), we get a palindrome (242342243242).

The spelling of 131231111111 in words is "one hundred thirty-one billion, two hundred thirty-one million, one hundred eleven thousand, one hundred eleven".