Hex #15616b or rgb(21,97,107) in RGB space is the tint of cyan. It has hue angle of 186.98 degrees, value = 42 and saturation = 80. #15616b can be obtained by mixing 4 colors: 1 drop of yellow, 3 drops of blue, 3 drops of cyan, 5 drops of black.
Nearest safe hex - #006666. Below you can see the block with #15616b color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #15616b to the mixer and play with it.