13813565 has 4 divisors (see below), whose sum is σ = 16576284. Its totient is φ = 11050848.

The previous prime is 13813561. The next prime is 13813567. The reversal of 13813565 is 56531831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56531831 = 5087 ⋅11113.

It can be written as a sum of positive squares in 2 ways, for example, as 8916196 + 4897369 = 2986^2 + 2213^2 .

It is a cyclic number.

It is not a de Polignac number, because 13813565 - 2² = 13813561 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13813561) 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, 1381352 + ... + 1381361.

It is an arithmetic number, because the mean of its divisors is an integer number (4144071).

Almost surely, 2^13813565 is an apocalyptic number.

It is an amenable number.

13813565 is a deficient number, since it is larger than the sum of its proper divisors (2762719).

13813565 is an equidigital number, since it uses as much as digits as its factorization.

13813565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2762718.

The product of its digits is 10800, while the sum is 32.

The square root of 13813565 is about 3716.6604633730. The cubic root of 13813565 is about 239.9395970677.

The spelling of 13813565 in words is "thirteen million, eight hundred thirteen thousand, five hundred sixty-five".