Hex #66d5cc or rgb(102,213,204) in RGB space is the tint of cyan. It has hue angle of 175.14 degrees, value = 84 and saturation = 52. #66d5cc can be obtained by mixing 4 colors: 1 drop of red, 5 drops of cyan, 1 drop of green, 3 drops of white.
Nearest safe hex - #66cccc. Below you can see the block with #66d5cc color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #66d5cc to the mixer and play with it.