Hex #55797b or rgb(85,121,123) in RGB space is the tint of cyan. It has hue angle of 183.16 degrees, value = 48 and saturation = 31. #55797b can be obtained by mixing 4 colors: 2 drops of blue, 1 drop of green, 3 drops of white, 3 drops of black.
Nearest safe hex - #666666. Below you can see the block with #55797b color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #55797b to the mixer and play with it.