Hex #556464 or rgb(85,100,100) in RGB space is the tint of cyan. It has hue angle of 180.00 degrees, value = 39 and saturation = 15. #556464 can be obtained by mixing 4 colors: 2 drops of magenta, 1 drop of cyan, 2 drops of green, 1 drop of black.
Nearest safe hex - #666666. Below you can see the block with #556464 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #556464 to the mixer and play with it.