Hex #66909f or rgb(102,144,159) in RGB space is the tint of bluish cian. It has hue angle of 195.79 degrees, value = 62 and saturation = 36. #66909f can be obtained by mixing 4 colors: 5 drops of magenta, 5 drops of cyan, 4 drops of green, 1 drop of white.
Nearest safe hex - #669999. Below you can see the block with #66909f color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #66909f to the mixer and play with it.