13218109 has 8 divisors (see below), whose sum is σ = 13388760. Its totient is φ = 13048896.

The previous prime is 13218097. The next prime is 13218131. The reversal of 13218109 is 90181231.

It can be written as a sum of positive squares in 4 ways, for example, as 11902500 + 1315609 = 3450^2 + 1147^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 13218109 - 2¹⁷ = 13087037 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 (13218199) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44967 + ... + 45259.

It is an arithmetic number, because the mean of its divisors is an integer number (1673595).

Almost surely, 2^13218109 is an apocalyptic number.

It is an amenable number.

13218109 is a deficient number, since it is larger than the sum of its proper divisors (170651).

13218109 is a wasteful number, since it uses less digits than its factorization.

13218109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 719.

The product of its (nonzero) digits is 432, while the sum is 25.

The square root of 13218109 is about 3635.6717398577. The cubic root of 13218109 is about 236.4411753809.

The spelling of 13218109 in words is "thirteen million, two hundred eighteen thousand, one hundred nine".