Hex #665900 or rgb(102,89,0) in RGB space is the tint of khaki. It has hue angle of 52.35 degrees, value = 40 and saturation = 100. #665900 can be obtained by mixing 4 colors: 3 drops of yellow, 1 drop of red, 1 drop of green, 5 drops of black.
Nearest safe hex - #666600. Below you can see the block with #665900 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #665900 to the mixer and play with it.