12657209 has 2 divisors, whose sum is σ = 12657210. Its totient is φ = 12657208.

The previous prime is 12657191. The next prime is 12657217. The reversal of 12657209 is 90275621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9517225 + 3139984 = 3085^2 + 1772^2 .

It is a cyclic number.

It is not a de Polignac number, because 12657209 - 2²⁰ = 11608633 is a prime.

It is not a weakly prime, because it can be changed into another prime (12657289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6328604 + 6328605.

It is an arithmetic number, because the mean of its divisors is an integer number (6328605).

Almost surely, 2^12657209 is an apocalyptic number.

It is an amenable number.

12657209 is a deficient number, since it is larger than the sum of its proper divisors (1).

12657209 is an equidigital number, since it uses as much as digits as its factorization.

12657209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 12657209 is about 3557.6971484375. The cubic root of 12657209 is about 233.0483238936.

The spelling of 12657209 in words is "twelve million, six hundred fifty-seven thousand, two hundred nine".