Hex #559fda or rgb(85,159,218) in RGB space is the tint of blue. It has hue angle of 206.62 degrees, value = 85 and saturation = 61. #559fda can be obtained by mixing 4 colors: 1 drop of magenta, 3 drops of blue, 3 drops of cyan, 2 drops of white.
Nearest safe hex - #6699cc. Below you can see the block with #559fda color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #559fda to the mixer and play with it.