Hex #557f42 or rgb(85,127,66) in RGB space is the tint of grass green. It has hue angle of 101.31 degrees, value = 50 and saturation = 48. #557f42 can be obtained by mixing 4 colors: 1 drop of red, 2 drops of magenta, 1 drop of cyan, 5 drops of green.
Nearest safe hex - #666633. Below you can see the block with #557f42 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #557f42 to the mixer and play with it.