Hex #557385 or rgb(85,115,133) in RGB space is the tint of blue. It has hue angle of 202.50 degrees, value = 52 and saturation = 36. #557385 can be obtained by mixing 4 colors: 1 drop of yellow, 4 drops of blue, 2 drops of white, 2 drops of black.
Nearest safe hex - #666699. Below you can see the block with #557385 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #557385 to the mixer and play with it.