Subtracting from 7986 its reverse (6897), we obtain a square (1089 = 332).
It is a happy number.
It is a Curzon number.
It is a nialpdrome in base 11.
It is an unprimeable number.
27986 is an apocalyptic number.
It is a practical number, because each smaller number is the sum of distinct divisors of 7986, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8784).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
7986 is a wasteful number, since it uses less digits than its factorization.
7986 is an evil number, because the sum of its binary digits is even.
The square root of 7986 is about 89.3644224510. The cubic root of 7986 is about 19.9883265212.
The spelling of 7986 in words is "seven thousand, nine hundred eighty-six".