Hex #66cb00 or rgb(102,203,0) in RGB space is the tint of olive. It has hue angle of 89.85 degrees, value = 80 and saturation = 100. #66cb00 can be obtained by mixing 2 colors: 2 drops of yellow, 3 drops of green.
Nearest safe hex - #66cc00. Below you can see the block with #66cb00 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #66cb00 to the mixer and play with it.