Hex #558083 or rgb(85,128,131) in RGB space is the tint of cyan. It has hue angle of 183.91 degrees, value = 51 and saturation = 35. #558083 can be obtained by mixing 4 colors: 4 drops of blue, 2 drops of green, 5 drops of white, 4 drops of black.
Nearest safe hex - #669999. Below you can see the block with #558083 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #558083 to the mixer and play with it.