Hex #403c00 or rgb(64,60,0) in RGB space is the tint of yellow. It has hue angle of 56.25 degrees, value = 25 and saturation = 100. #403c00 can be obtained by mixing 3 colors: 3 drops of red, 4 drops of green, 5 drops of black.
Nearest safe hex - #333300. Below you can see the block with #403c00 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #403c00 to the mixer and play with it.