Hex #557a55 or rgb(85,122,85) in RGB space is the tint of green. It has hue angle of 120.00 degrees, value = 48 and saturation = 30. #557a55 can be obtained by mixing 4 colors: 1 drop of yellow, 1 drop of cyan, 1 drop of white, 3 drops of black.
Nearest safe hex - #666666. Below you can see the block with #557a55 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #557a55 to the mixer and play with it.