Hex #99d577 or rgb(153,213,119) in RGB space is the tint of grass green. It has hue angle of 98.30 degrees, value = 84 and saturation = 44. #99d577 can be obtained by mixing 3 colors: 5 drops of yellow, 1 drop of magenta, 4 drops of cyan.
Nearest safe hex - #99cc66. Below you can see the block with #99d577 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #99d577 to the mixer and play with it.