Hex #557a9c or rgb(85,122,156) in RGB space is the tint of blue. It has hue angle of 208.73 degrees, value = 61 and saturation = 46. #557a9c can be obtained by mixing 4 colors: 1 drop of magenta, 2 drops of cyan, 1 drop of white, 2 drops of black.
Nearest safe hex - #666699. Below you can see the block with #557a9c color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #557a9c to the mixer and play with it.