Hex #555c5b or rgb(85,92,91) in RGB space is the tint of greenish cian. It has hue angle of 171.43 degrees, value = 36 and saturation = 8. #555c5b can be obtained by mixing 4 colors: 5 drops of magenta, 2 drops of cyan, 5 drops of green, 3 drops of black.
Nearest safe hex - #666666. Below you can see the block with #555c5b color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #555c5b to the mixer and play with it.