Hex #153647 or rgb(21,54,71) in RGB space is the tint of bluish cian. It has hue angle of 200.40 degrees, value = 28 and saturation = 70. #153647 can be obtained by mixing 4 colors: 1 drop of magenta, 4 drops of blue, 2 drops of green, 5 drops of black.
Nearest safe hex - #003333. Below you can see the block with #153647 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #153647 to the mixer and play with it.