13687809 has 16 divisors (see below), whose sum is σ = 19682880. Its totient is φ = 8432640.

The previous prime is 13687801. The next prime is 13687811. The reversal of 13687809 is 90878631.

It is not a de Polignac number, because 13687809 - 2³ = 13687801 is a prime.

It is a super-2 number, since 2×13687809² = 374712230440962, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (13687801) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 592 + ... + 5265.

It is an arithmetic number, because the mean of its divisors is an integer number (1230180).

Almost surely, 2^13687809 is an apocalyptic number.

13687809 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

13687809 is a deficient number, since it is larger than the sum of its proper divisors (5995071).

13687809 is a wasteful number, since it uses less digits than its factorization.

13687809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5920.

The product of its (nonzero) digits is 72576, while the sum is 42.

The square root of 13687809 is about 3699.7039070715. The cubic root of 13687809 is about 239.2092551778.

The spelling of 13687809 in words is "thirteen million, six hundred eighty-seven thousand, eight hundred nine".