13568409 has 12 divisors (see below), whose sum is σ = 19650852. Its totient is φ = 9021600.

The previous prime is 13568389. The next prime is 13568419. The reversal of 13568409 is 90486531.

13568409 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 4995225 + 8573184 = 2235^2 + 2928^2 .

It is not a de Polignac number, because 13568409 - 2⁸ = 13568153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (13568419) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1999 + ... + 5579.

It is an arithmetic number, because the mean of its divisors is an integer number (1637571).

Almost surely, 2^13568409 is an apocalyptic number.

It is an amenable number.

13568409 is a deficient number, since it is larger than the sum of its proper divisors (6082443).

13568409 is a wasteful number, since it uses less digits than its factorization.

13568409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4008 (or 4005 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 13568409 is about 3683.5321364147. The cubic root of 13568409 is about 238.5116748633.

The spelling of 13568409 in words is "thirteen million, five hundred sixty-eight thousand, four hundred nine".