Hex #559a00 or rgb(85,154,0) in RGB space is the tint of olive. It has hue angle of 86.88 degrees, value = 60 and saturation = 100. #559a00 can be obtained by mixing 3 colors: 4 drops of yellow, 5 drops of green, 3 drops of black.
Nearest safe hex - #669900. Below you can see the block with #559a00 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #559a00 to the mixer and play with it.