13685 has 16 divisors (see below), whose sum is σ = 20736. Its totient is φ = 8448.

The previous prime is 13681. The next prime is 13687. The reversal of 13685 is 58631.

13685 = T₃₅ + T₃₆ + ... + T₄₉.

13685 = 1² + 2² + ... + 34².

13685 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 13685 - 2² = 13681 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

13685 is strictly pandigital in base 6.

It is a nialpdrome in base 11.

It is a self number, because there is not a number n which added to its sum of digits gives 13685.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13681) 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, 584 + ... + 606.

It is an arithmetic number, because the mean of its divisors is an integer number (1296).

2¹³⁶⁸⁵ is an apocalyptic number.

It is an amenable number.

13685 is a deficient number, since it is larger than the sum of its proper divisors (7051).

13685 is a wasteful number, since it uses less digits than its factorization.

13685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52.

The product of its digits is 720, while the sum is 23.

The square root of 13685 is about 116.9829047340. The cubic root of 13685 is about 23.9192890621.

13685 divided by its sum of digits (23) gives a palindrome (595).

The spelling of 13685 in words is "thirteen thousand, six hundred eighty-five".