Hex #5d918b or rgb(93,145,139) in RGB space is the tint of cyan. It has hue angle of 173.08 degrees, value = 57 and saturation = 36. #5d918b can be obtained by mixing 4 colors: 3 drops of blue, 2 drops of green, 4 drops of white, 2 drops of black.
Nearest safe hex - #669999. Below you can see the block with #5d918b color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #5d918b to the mixer and play with it.