12915209 has 2 divisors, whose sum is σ = 12915210. Its totient is φ = 12915208.

The previous prime is 12915197. The next prime is 12915239. The reversal of 12915209 is 90251921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12759184 + 156025 = 3572^2 + 395^2 .

It is a cyclic number.

It is not a de Polignac number, because 12915209 - 2⁸ = 12914953 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (12915239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6457604 + 6457605.

It is an arithmetic number, because the mean of its divisors is an integer number (6457605).

Almost surely, 2^12915209 is an apocalyptic number.

It is an amenable number.

12915209 is a deficient number, since it is larger than the sum of its proper divisors (1).

12915209 is an equidigital number, since it uses as much as digits as its factorization.

12915209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1620, while the sum is 29.

The square root of 12915209 is about 3593.7736434005. The cubic root of 12915209 is about 234.6211429840.

The spelling of 12915209 in words is "twelve million, nine hundred fifteen thousand, two hundred nine".