12665309 has 2 divisors, whose sum is σ = 12665310. Its totient is φ = 12665308.

The previous prime is 12665297. The next prime is 12665311. The reversal of 12665309 is 90356621.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12581209 + 84100 = 3547^2 + 290^2 .

It is an emirp because it is prime and its reverse (90356621) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12665309 - 2⁴ = 12665293 is a prime.

Together with 12665311, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12665509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6332654 + 6332655.

It is an arithmetic number, because the mean of its divisors is an integer number (6332655).

Almost surely, 2^12665309 is an apocalyptic number.

It is an amenable number.

12665309 is a deficient number, since it is larger than the sum of its proper divisors (1).

12665309 is an equidigital number, since it uses as much as digits as its factorization.

12665309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9720, while the sum is 32.

The square root of 12665309 is about 3558.8353431987. The cubic root of 12665309 is about 233.0980265016.

The spelling of 12665309 in words is "twelve million, six hundred sixty-five thousand, three hundred nine".