Hex #557498 or rgb(85,116,152) in RGB space is the tint of blue. It has hue angle of 212.24 degrees, value = 60 and saturation = 44. #557498 can be obtained by mixing 4 colors: 1 drop of red, 5 drops of blue, 1 drop of green, 2 drops of white.
Nearest safe hex - #666699. Below you can see the block with #557498 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #557498 to the mixer and play with it.