There are 9 colors as well as "no color" so 10 possible choices for each cell.
There are icon sizes of 4*4, 5*5, 6*6, 8*8, 10*10, and 15*15.
Thus,
10^16+10^25+10^36+10^64+10^100+10^225
No this is the number
1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000010000000000000000000000000001000000000010000000010000000000000000
While 10^225 is
1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000