12945409 has 4 divisors (see below), whose sum is σ = 13189716. Its totient is φ = 12701104.

The previous prime is 12945391. The next prime is 12945419. The reversal of 12945409 is 90454921.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4840000 + 8105409 = 2200^2 + 2847^2 .

It is a cyclic number.

It is not a de Polignac number, because 12945409 - 2⁵ = 12945377 is a prime.

It is a super-2 number, since 2×12945409² = 335167228354562, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12945419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122074 + ... + 122179.

It is an arithmetic number, because the mean of its divisors is an integer number (3297429).

Almost surely, 2^12945409 is an apocalyptic number.

It is an amenable number.

12945409 is a deficient number, since it is larger than the sum of its proper divisors (244307).

12945409 is an equidigital number, since it uses as much as digits as its factorization.

12945409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244306.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 12945409 is about 3597.9729015100. The cubic root of 12945409 is about 234.8038743899.

The spelling of 12945409 in words is "twelve million, nine hundred forty-five thousand, four hundred nine".