Hex #559da1 or rgb(85,157,161) in RGB space is the tint of cyan. It has hue angle of 183.16 degrees, value = 63 and saturation = 47. #559da1 can be obtained by mixing 3 colors: 4 drops of blue, 2 drops of green, 3 drops of white.
Nearest safe hex - #669999. Below you can see the block with #559da1 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #559da1 to the mixer and play with it.