Hex #555f55 or rgb(85,95,85) in RGB space is the tint of green. It has hue angle of 120.00 degrees, value = 37 and saturation = 11. #555f55 can be obtained by mixing 4 colors: 1 drop of yellow, 4 drops of red, 5 drops of cyan, 5 drops of black.
Nearest safe hex - #666666. Below you can see the block with #555f55 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #555f55 to the mixer and play with it.