Hex #555b72 or rgb(85,91,114) in RGB space is the tint of blue violet. It has hue angle of 227.59 degrees, value = 45 and saturation = 25. #555b72 can be obtained by mixing 4 colors: 2 drops of red, 1 drop of blue, 2 drops of cyan, 1 drop of black.
Nearest safe hex - #666666. Below you can see the block with #555b72 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #555b72 to the mixer and play with it.