Hex #6691a5 or rgb(102,145,165) in RGB space is the tint of bluish cian. It has hue angle of 199.05 degrees, value = 65 and saturation = 38. #6691a5 can be obtained by mixing 4 colors: 3 drops of yellow, 3 drops of magenta, 4 drops of blue, 5 drops of cyan.
Nearest safe hex - #669999. Below you can see the block with #6691a5 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #6691a5 to the mixer and play with it.