Hex #554d39 or rgb(85,77,57) in RGB space is the tint of khaki. It has hue angle of 42.86 degrees, value = 33 and saturation = 33. #554d39 can be obtained by mixing 4 colors: 1 drop of red, 1 drop of green, 2 drops of white, 5 drops of black.
Nearest safe hex - #666633. Below you can see the block with #554d39 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #554d39 to the mixer and play with it.