Hex #66d4b5 or rgb(102,212,181) in RGB space is the tint of greenish cian. It has hue angle of 163.09 degrees, value = 83 and saturation = 52. #66d4b5 can be obtained by mixing 4 colors: 1 drop of magenta, 5 drops of cyan, 4 drops of green, 5 drops of white.
Nearest safe hex - #66cccc. Below you can see the block with #66d4b5 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #66d4b5 to the mixer and play with it.