Hex #668e4f or rgb(102,142,79) in RGB space is the tint of grass green. It has hue angle of 98.10 degrees, value = 56 and saturation = 44. #668e4f can be obtained by mixing 4 colors: 5 drops of yellow, 1 drop of magenta, 4 drops of cyan, 5 drops of black.
Nearest safe hex - #669966. Below you can see the block with #668e4f color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #668e4f to the mixer and play with it.