Hex #557072 or rgb(85,112,114) in RGB space is the tint of cyan. It has hue angle of 184.14 degrees, value = 45 and saturation = 25. #557072 can be obtained by mixing 4 colors: 2 drops of blue, 1 drop of green, 4 drops of white, 5 drops of black.
Nearest safe hex - #666666. Below you can see the block with #557072 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #557072 to the mixer and play with it.