13686809 has 2 divisors, whose sum is σ = 13686810. Its totient is φ = 13686808.

The previous prime is 13686787. The next prime is 13686833. The reversal of 13686809 is 90868631.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13579225 + 107584 = 3685^2 + 328^2 .

It is a cyclic number.

It is not a de Polignac number, because 13686809 - 2⁸ = 13686553 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (13686839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6843404 + 6843405.

It is an arithmetic number, because the mean of its divisors is an integer number (6843405).

Almost surely, 2^13686809 is an apocalyptic number.

It is an amenable number.

13686809 is a deficient number, since it is larger than the sum of its proper divisors (1).

13686809 is an equidigital number, since it uses as much as digits as its factorization.

13686809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 62208, while the sum is 41.

The square root of 13686809 is about 3699.5687586528. The cubic root of 13686809 is about 239.2034296757.

The spelling of 13686809 in words is "thirteen million, six hundred eighty-six thousand, eight hundred nine".