Hex #559439 or rgb(85,148,57) in RGB space is the tint of grass green. It has hue angle of 101.54 degrees, value = 58 and saturation = 61. #559439 can be obtained by mixing 4 colors: 4 drops of yellow, 4 drops of blue, 3 drops of green, 1 drop of black.
Nearest safe hex - #669933. Below you can see the block with #559439 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #559439 to the mixer and play with it.