Hex #667f89 or rgb(102,127,137) in RGB space is the tint of bluish cian. It has hue angle of 197.14 degrees, value = 54 and saturation = 26. #667f89 can be obtained by mixing 4 colors: 2 drops of magenta, 3 drops of blue, 3 drops of green, 2 drops of white.
Nearest safe hex - #666699. Below you can see the block with #667f89 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #667f89 to the mixer and play with it.