Hex #663f7d or rgb(102,63,125) in RGB space is the tint of purple magenta. It has hue angle of 277.74 degrees, value = 49 and saturation = 50. #663f7d can be obtained by mixing 4 colors: 1 drop of red, 5 drops of magenta, 4 drops of cyan, 5 drops of black.
Nearest safe hex - #663366. Below you can see the block with #663f7d color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #663f7d to the mixer and play with it.