Hex #278bb7 or rgb(39,139,183) in RGB space is the tint of bluish cian. It has hue angle of 198.33 degrees, value = 72 and saturation = 79. #278bb7 can be obtained by mixing 4 colors: 5 drops of blue, 4 drops of cyan, 2 drops of white, 2 drops of black.
Nearest safe hex - #3399cc. Below you can see the block with #278bb7 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #278bb7 to the mixer and play with it.