13564561 has 4 divisors (see below), whose sum is σ = 13623012. Its totient is φ = 13506112.

The previous prime is 13564553. The next prime is 13564601. The reversal of 13564561 is 16546531.

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 5612161 + 7952400 = 2369^2 + 2820^2 .

It is a cyclic number.

It is not a de Polignac number, because 13564561 - 2³ = 13564553 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13564361) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28876 + ... + 29341.

It is an arithmetic number, because the mean of its divisors is an integer number (3405753).

Almost surely, 2^13564561 is an apocalyptic number.

It is an amenable number.

13564561 is a deficient number, since it is larger than the sum of its proper divisors (58451).

13564561 is an equidigital number, since it uses as much as digits as its factorization.

13564561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58450.

The product of its digits is 10800, while the sum is 31.

The square root of 13564561 is about 3683.0097746273. The cubic root of 13564561 is about 238.4891254324.

The spelling of 13564561 in words is "thirteen million, five hundred sixty-four thousand, five hundred sixty-one".