231040309 has 2 divisors, whose sum is σ = 231040310. Its totient is φ = 231040308.

The previous prime is 231040301. The next prime is 231040331. The reversal of 231040309 is 903040132.

It is an a-pointer prime, because the next prime (231040331) can be obtained adding 231040309 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 173659684 + 57380625 = 13178^2 + 7575^2 .

It is a cyclic number.

It is not a de Polignac number, because 231040309 - 2³ = 231040301 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 231040309.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231040301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115520154 + 115520155.

It is an arithmetic number, because the mean of its divisors is an integer number (115520155).

Almost surely, 2^231040309 is an apocalyptic number.

It is an amenable number.

231040309 is a deficient number, since it is larger than the sum of its proper divisors (1).

231040309 is an equidigital number, since it uses as much as digits as its factorization.

231040309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 22.

The square root of 231040309 is about 15200.0101644703. The cubic root of 231040309 is about 613.6149313071.

The spelling of 231040309 in words is "two hundred thirty-one million, forty thousand, three hundred nine".