12566409 has 4 divisors (see below), whose sum is σ = 16755216. Its totient is φ = 8377604.

The previous prime is 12566369. The next prime is 12566419. The reversal of 12566409 is 90466521.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12566409 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12566409.

It is not an unprimeable number, because it can be changed into a prime (12566419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2094399 + ... + 2094404.

It is an arithmetic number, because the mean of its divisors is an integer number (4188804).

Almost surely, 2^12566409 is an apocalyptic number.

It is an amenable number.

12566409 is a deficient number, since it is larger than the sum of its proper divisors (4188807).

12566409 is an equidigital number, since it uses as much as digits as its factorization.

12566409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4188806.

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 12566409 is about 3544.9131160016. The cubic root of 12566409 is about 232.4897070250.

The spelling of 12566409 in words is "twelve million, five hundred sixty-six thousand, four hundred nine".