Hex #555444 or rgb(85,84,68) in RGB space is the tint of yellow. It has hue angle of 56.47 degrees, value = 33 and saturation = 20. #555444 can be obtained by mixing 4 colors: 4 drops of red, 1 drop of magenta, 5 drops of blue, 5 drops of green.
Nearest safe hex - #666633. Below you can see the block with #555444 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #555444 to the mixer and play with it.