39,916,800 color combinations are possible
Here, we want to get the possible number of color combinations possible.
Since any number of colors can be chosen, there are no restrictions here
That means the number of possible color combinations will be;
11! = 11 * 10 * 9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1 = 39,916,800 color combinations