13809217 has 4 divisors (see below), whose sum is σ = 13826260. Its totient is φ = 13792176.

The previous prime is 13809209. The next prime is 13809227. The reversal of 13809217 is 71290831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71290831 = 19 ⋅3752149.

It can be written as a sum of positive squares in 2 ways, for example, as 3207681 + 10601536 = 1791^2 + 3256^2 .

It is a cyclic number.

It is not a de Polignac number, because 13809217 - 2³ = 13809209 is a prime.

It is a deceptive number, since it divides R_13809216.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13809227) 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, 7242 + ... + 8947.

It is an arithmetic number, because the mean of its divisors is an integer number (3456565).

Almost surely, 2^13809217 is an apocalyptic number.

It is an amenable number.

13809217 is a deficient number, since it is larger than the sum of its proper divisors (17043).

13809217 is an equidigital number, since it uses as much as digits as its factorization.

13809217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17042.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 13809217 is about 3716.0754836252. The cubic root of 13809217 is about 239.9144197185.

The spelling of 13809217 in words is "thirteen million, eight hundred nine thousand, two hundred seventeen".