1231320317 has 2 divisors, whose sum is σ = 1231320318. Its totient is φ = 1231320316.

The previous prime is 1231320281. The next prime is 1231320427. The reversal of 1231320317 is 7130231321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 615734596 + 615585721 = 24814^2 + 24811^2 .

It is a cyclic number.

It is not a de Polignac number, because 1231320317 - 2¹⁰ = 1231319293 is a prime.

It is a super-2 number, since 2×1231320317² = 3032299446113960978, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1231320292 and 1231320301.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1231320017) 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, 615660158 + 615660159.

It is an arithmetic number, because the mean of its divisors is an integer number (615660159).

Almost surely, 2^1231320317 is an apocalyptic number.

It is an amenable number.

1231320317 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231320317 is an equidigital number, since it uses as much as digits as its factorization.

1231320317 is an odious number, because the sum of its binary digits is odd.

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

The square root of 1231320317 is about 35090.1740805029. The cubic root of 1231320317 is about 1071.8245044475.

Adding to 1231320317 its reverse (7130231321), we get a palindrome (8361551638).

The spelling of 1231320317 in words is "one billion, two hundred thirty-one million, three hundred twenty thousand, three hundred seventeen".