Hex #668191 or rgb(102,129,145) in RGB space is the tint of bluish cian. It has hue angle of 202.33 degrees, value = 57 and saturation = 30. #668191 can be obtained by mixing 4 colors: 1 drop of yellow, 4 drops of blue, 3 drops of white, 2 drops of black.
Nearest safe hex - #669999. Below you can see the block with #668191 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #668191 to the mixer and play with it.