13031309 has 2 divisors, whose sum is σ = 13031310. Its totient is φ = 13031308.

The previous prime is 13031261. The next prime is 13031329. The reversal of 13031309 is 90313031.

13031309 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (13031329) can be obtained adding 13031309 to its sum of digits (20).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8094025 + 4937284 = 2845^2 + 2222^2 .

It is an emirp because it is prime and its reverse (90313031) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13031309 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13031329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6515654 + 6515655.

It is an arithmetic number, because the mean of its divisors is an integer number (6515655).

Almost surely, 2^13031309 is an apocalyptic number.

It is an amenable number.

13031309 is a deficient number, since it is larger than the sum of its proper divisors (1).

13031309 is an equidigital number, since it uses as much as digits as its factorization.

13031309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 243, while the sum is 20.

The square root of 13031309 is about 3609.8904415508. The cubic root of 13031309 is about 235.3220813787.

The spelling of 13031309 in words is "thirteen million, thirty-one thousand, three hundred nine".