Hex #15a9a3 or rgb(21,169,163) in RGB space is the tint of cyan. It has hue angle of 177.57 degrees, value = 66 and saturation = 88. #15a9a3 can be obtained by mixing 4 colors: 4 drops of blue, 4 drops of cyan, 3 drops of green, 1 drop of white.
Nearest safe hex - #009999. Below you can see the block with #15a9a3 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #15a9a3 to the mixer and play with it.