231312317 has 2 divisors, whose sum is σ = 231312318. Its totient is φ = 231312316.

The previous prime is 231312281. The next prime is 231312329. The reversal of 231312317 is 713213132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 189915961 + 41396356 = 13781^2 + 6434^2 .

It is a cyclic number.

It is not a de Polignac number, because 231312317 - 2¹⁸ = 231050173 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 231312292 and 231312301.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231312377) 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 as a sum of consecutive naturals, namely, 115656158 + 115656159.

It is an arithmetic number, because the mean of its divisors is an integer number (115656159).

Almost surely, 2^231312317 is an apocalyptic number.

It is an amenable number.

231312317 is a deficient number, since it is larger than the sum of its proper divisors (1).

231312317 is an equidigital number, since it uses as much as digits as its factorization.

231312317 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 756, while the sum is 23.

The square root of 231312317 is about 15208.9551580639. The cubic root of 231312317 is about 613.8556435771.

Adding to 231312317 its reverse (713213132), we get a palindrome (944525449).

The spelling of 231312317 in words is "two hundred thirty-one million, three hundred twelve thousand, three hundred seventeen".