Hex #669499 or rgb(102,148,153) in RGB space is the tint of cyan. It has hue angle of 185.88 degrees, value = 60 and saturation = 33. #669499 can be obtained by mixing 4 colors: 1 drop of red, 3 drops of cyan, 3 drops of white, 3 drops of black.
Nearest safe hex - #669999. Below you can see the block with #669499 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #669499 to the mixer and play with it.