11985 has 16 divisors (see below), whose sum is σ = 20736.
Its totient is φ = 5888.
The previous prime is 11981. The next prime is 11987. The reversal of 11985 is 58911.
11985 = 302 + 312 + ... + 392.
It is a cyclic number.
It is not a de Polignac number, because 11985 - 22 = 11981 is a prime.
Its product of digits (360) is a multiple of the sum of its prime divisors (72).
It is a Curzon number.
It is a plaindrome in base 13.
It is not an unprimeable number, because it can be changed into a prime (11981) 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, 232 + ... + 278.
It is an arithmetic number, because the mean of its divisors is an integer number (1296).
211985 is an apocalyptic number.
11985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.
It is an amenable number.
11985 is a deficient number, since it is larger than the sum of its proper divisors (8751).
11985 is a wasteful number, since it uses less digits than its factorization.
11985 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 72.
The product of its digits is 360, while the sum is 24.
The square root of 11985 is about 109.4760247726.
The cubic root of 11985 is about 22.8847415882.
The spelling of 11985 in words is "eleven thousand, nine hundred eighty-five".