Hex #55b839 or rgb(85,184,57) in RGB space is the tint of grass green. It has hue angle of 106.77 degrees, value = 72 and saturation = 69. #55b839 can be obtained by mixing 4 colors: 1 drop of yellow, 5 drops of green, 2 drops of white, 1 drop of black.
Nearest safe hex - #66cc33. Below you can see the block with #55b839 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #55b839 to the mixer and play with it.