13859209 has 12 divisors (see below), whose sum is σ = 17362884. Its totient is φ = 10965024.

The previous prime is 13859177. The next prime is 13859243. The reversal of 13859209 is 90295831.

It can be written as a sum of positive squares in 2 ways, for example, as 7683984 + 6175225 = 2772^2 + 2485^2 .

It is not a de Polignac number, because 13859209 - 2⁵ = 13859177 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13859249) 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 11 ways as a sum of consecutive naturals, for example, 10242 + ... + 11515.

It is an arithmetic number, because the mean of its divisors is an integer number (1446907).

Almost surely, 2^13859209 is an apocalyptic number.

It is an amenable number.

13859209 is a deficient number, since it is larger than the sum of its proper divisors (3503675).

13859209 is a wasteful number, since it uses less digits than its factorization.

13859209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21784 (or 21777 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 37.

The square root of 13859209 is about 3722.7958579541. The cubic root of 13859209 is about 240.2035830463.

The spelling of 13859209 in words is "thirteen million, eight hundred fifty-nine thousand, two hundred nine".