11685 has 16 divisors (see below), whose sum is σ = 20160. Its totient is φ = 5760.

The previous prime is 11681. The next prime is 11689. The reversal of 11685 is 58611.

It is an interprime number because it is at equal distance from previous prime (11681) and next prime (11689).

It is not a de Polignac number, because 11685 - 2² = 11681 is a prime.

It is a Curzon number.

It is a nialpdrome in base 5 and base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11681) 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, 265 + ... + 305.

It is an arithmetic number, because the mean of its divisors is an integer number (1260).

2¹¹⁶⁸⁵ is an apocalyptic number.

11685 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

11685 is a deficient number, since it is larger than the sum of its proper divisors (8475).

11685 is a wasteful number, since it uses less digits than its factorization.

11685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68.

The product of its digits is 240, while the sum is 21.

The square root of 11685 is about 108.0971785016. The cubic root of 11685 is about 22.6921809965.

Subtracting from 11685 its sum of digits (21), we obtain a square (11664 = 108²).

It can be divided in two parts, 11 and 685, that added together give a palindrome (696).

The spelling of 11685 in words is "eleven thousand, six hundred eighty-five".