Hex #668c66 or rgb(102,140,102) in RGB space is the tint of green. It has hue angle of 120.00 degrees, value = 55 and saturation = 27. #668c66 can be obtained by mixing 4 colors: 3 drops of magenta, 1 drop of cyan, 5 drops of green, 1 drop of white.
Nearest safe hex - #669966. Below you can see the block with #668c66 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #668c66 to the mixer and play with it.