-4 is an even number.
-4 is a Harshad number, which means it is divisible by the sum of its digits (4 = 4, and -4 is divisible by 4).
In binary, -4 is represented as 1111111111111111111111111111111111111111111111111111111111111100.
In hex, -4 is represented as fffffffffffffffc.