Hex #004039 or rgb(0,64,57) in RGB space is the tint of cyan. It has hue angle of 173.44 degrees, value = 25 and saturation = 100. #004039 can be obtained by mixing 3 colors: 3 drops of blue, 2 drops of green, 4 drops of black.
Nearest safe hex - #003333. Below you can see the block with #004039 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #004039 to the mixer and play with it.