12905609 has 4 divisors (see below), whose sum is σ = 13350660. Its totient is φ = 12460560.

The previous prime is 12905603. The next prime is 12905639. The reversal of 12905609 is 90650921.

12905609 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90650921 = 47 ⋅1928743.

It can be written as a sum of positive squares in 2 ways, for example, as 9765625 + 3139984 = 3125^2 + 1772^2 .

It is a cyclic number.

It is not a de Polignac number, because 12905609 - 2²⁰ = 11857033 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12905603) 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 in 3 ways as a sum of consecutive naturals, for example, 222482 + ... + 222539.

It is an arithmetic number, because the mean of its divisors is an integer number (3337665).

Almost surely, 2^12905609 is an apocalyptic number.

It is an amenable number.

12905609 is a deficient number, since it is larger than the sum of its proper divisors (445051).

12905609 is an equidigital number, since it uses as much as digits as its factorization.

12905609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 445050.

The product of its (nonzero) digits is 4860, while the sum is 32.

The square root of 12905609 is about 3592.4377517224. The cubic root of 12905609 is about 234.5629965183.

The spelling of 12905609 in words is "twelve million, nine hundred five thousand, six hundred nine".