231307309 has 2 divisors, whose sum is σ = 231307310. Its totient is φ = 231307308.

The previous prime is 231307283. The next prime is 231307319. The reversal of 231307309 is 903703132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 229674025 + 1633284 = 15155^2 + 1278^2 .

It is a cyclic number.

It is not a de Polignac number, because 231307309 - 2⁹ = 231306797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231307319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115653654 + 115653655.

It is an arithmetic number, because the mean of its divisors is an integer number (115653655).

Almost surely, 2^231307309 is an apocalyptic number.

It is an amenable number.

231307309 is a deficient number, since it is larger than the sum of its proper divisors (1).

231307309 is an equidigital number, since it uses as much as digits as its factorization.

231307309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3402, while the sum is 28.

The square root of 231307309 is about 15208.7905173291. The cubic root of 231307309 is about 613.8512134754.

The spelling of 231307309 in words is "two hundred thirty-one million, three hundred seven thousand, three hundred nine".