Hex #663a33 or rgb(102,58,51) in RGB space is the tint of orange red. It has hue angle of 8.24 degrees, value = 40 and saturation = 50. #663a33 can be obtained by mixing 4 colors: 4 drops of red, 3 drops of blue, 2 drops of green, 1 drop of black.
Nearest safe hex - #663333. Below you can see the block with #663a33 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #663a33 to the mixer and play with it.