Hex #555a9d or rgb(85,90,157) in RGB space is the tint of violet. It has hue angle of 235.83 degrees, value = 62 and saturation = 46. #555a9d can be obtained by mixing 3 colors: 1 drop of red, 4 drops of blue, 1 drop of white.
Nearest safe hex - #666699. Below you can see the block with #555a9d color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #555a9d to the mixer and play with it.