Hex #558dd0 or rgb(85,141,208) in RGB space is the tint of blue. It has hue angle of 212.68 degrees, value = 82 and saturation = 59. #558dd0 can be obtained by mixing 4 colors: 1 drop of magenta, 4 drops of blue, 2 drops of cyan, 2 drops of white.
Nearest safe hex - #6699cc. Below you can see the block with #558dd0 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #558dd0 to the mixer and play with it.