Hex #551a55 or rgb(85,26,85) in RGB space is the tint of magenta. It has hue angle of 300.00 degrees, value = 33 and saturation = 69. #551a55 can be obtained by mixing 3 colors: 3 drops of magenta, 1 drop of cyan, 5 drops of black.
Nearest safe hex - #663366. Below you can see the block with #551a55 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #551a55 to the mixer and play with it.