Hex #66caaa or rgb(102,202,170) in RGB space is the tint of greenish cian. It has hue angle of 160.80 degrees, value = 79 and saturation = 50. #66caaa can be obtained by mixing 4 colors: 1 drop of magenta, 3 drops of cyan, 3 drops of green, 3 drops of white.
Nearest safe hex - #66cc99. Below you can see the block with #66caaa color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #66caaa to the mixer and play with it.