231311323181 has 2 divisors, whose sum is σ = 231311323182. Its totient is φ = 231311323180.

The previous prime is 231311323147. The next prime is 231311323247. The reversal of 231311323181 is 181323113132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 177177855625 + 54133467556 = 420925^2 + 232666^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-231311323181 is a prime.

It is a super-2 number, since 2×231311323181² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231311323981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115655661590 + 115655661591.

It is an arithmetic number, because the mean of its divisors is an integer number (115655661591).

Almost surely, 2^231311323181 is an apocalyptic number.

It is an amenable number.

231311323181 is a deficient number, since it is larger than the sum of its proper divisors (1).

231311323181 is an equidigital number, since it uses as much as digits as its factorization.

231311323181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2592, while the sum is 29.

The spelling of 231311323181 in words is "two hundred thirty-one billion, three hundred eleven million, three hundred twenty-three thousand, one hundred eighty-one".