Hex #555979 or rgb(85,89,121) in RGB space is the tint of violet. It has hue angle of 233.33 degrees, value = 47 and saturation = 30. #555979 can be obtained by mixing 4 colors: 4 drops of magenta, 3 drops of cyan, 2 drops of green, 3 drops of black.
Nearest safe hex - #666666. Below you can see the block with #555979 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #555979 to the mixer and play with it.