Hex #005b55 or rgb(0,91,85) in RGB space is the tint of cyan. It has hue angle of 176.04 degrees, value = 36 and saturation = 100. #005b55 can be obtained by mixing 4 colors: 1 drop of blue, 2 drops of cyan, 1 drop of green, 4 drops of black.
Nearest safe hex - #006666. Below you can see the block with #005b55 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #005b55 to the mixer and play with it.