Hex #15a5c7 or rgb(21,165,199) in RGB space is the tint of bluish cian. It has hue angle of 191.46 degrees, value = 78 and saturation = 89. #15a5c7 can be obtained by mixing 4 colors: 5 drops of blue, 5 drops of cyan, 1 drop of green, 1 drop of white.
Nearest safe hex - #0099cc. Below you can see the block with #15a5c7 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #15a5c7 to the mixer and play with it.