Hex #55b140 or rgb(85,177,64) in RGB space is the tint of grass green. It has hue angle of 108.85 degrees, value = 69 and saturation = 64. #55b140 can be obtained by mixing 4 colors: 4 drops of yellow, 3 drops of blue, 1 drop of cyan, 4 drops of green.
Nearest safe hex - #669933. Below you can see the block with #55b140 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #55b140 to the mixer and play with it.