Hex #5591d5 or rgb(85,145,213) in RGB space is the tint of blue. It has hue angle of 211.88 degrees, value = 84 and saturation = 60. #5591d5 can be obtained by mixing 4 colors: 1 drop of magenta, 2 drops of blue, 2 drops of cyan, 1 drop of white.
Nearest safe hex - #6699cc. Below you can see the block with #5591d5 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #5591d5 to the mixer and play with it.