Hex #667b55 or rgb(102,123,85) in RGB space is the tint of olive. It has hue angle of 93.16 degrees, value = 48 and saturation = 31. #667b55 can be obtained by mixing 4 colors: 1 drop of magenta, 2 drops of green, 1 drop of white, 1 drop of black.
Nearest safe hex - #666666. Below you can see the block with #667b55 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #667b55 to the mixer and play with it.