Hex #66c680 or rgb(102,198,128) in RGB space is the tint of bluish green. It has hue angle of 136.25 degrees, value = 78 and saturation = 48. #66c680 can be obtained by mixing 4 colors: 1 drop of cyan, 4 drops of green, 4 drops of white, 1 drop of black.
Nearest safe hex - #66cc99. Below you can see the block with #66c680 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #66c680 to the mixer and play with it.