Hex #555180 or rgb(85,81,128) in RGB space is the tint of violet. It has hue angle of 245.11 degrees, value = 50 and saturation = 37. #555180 can be obtained by mixing 4 colors: 3 drops of magenta, 3 drops of cyan, 1 drop of white, 5 drops of black.
Nearest safe hex - #666699. Below you can see the block with #555180 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #555180 to the mixer and play with it.