Hex #2b638f or rgb(43,99,143) in RGB space is the tint of blue. It has hue angle of 206.40 degrees, value = 56 and saturation = 70. #2b638f can be obtained by mixing 2 colors: 1 drop of yellow, 5 drops of blue.
Nearest safe hex - #336699. Below you can see the block with #2b638f color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #2b638f to the mixer and play with it.