Hex #66bb80 or rgb(102,187,128) in RGB space is the tint of bluish green. It has hue angle of 138.35 degrees, value = 73 and saturation = 45. #66bb80 can be obtained by mixing 3 colors: 4 drops of yellow, 3 drops of blue, 3 drops of cyan.
Nearest safe hex - #66cc99. Below you can see the block with #66bb80 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #66bb80 to the mixer and play with it.