Hex #666f5b or rgb(102,111,91) in RGB space is the tint of olive. It has hue angle of 87.00 degrees, value = 44 and saturation = 18. #666f5b can be obtained by mixing 4 colors: 2 drops of yellow, 4 drops of magenta, 4 drops of blue, 5 drops of green.
Nearest safe hex - #666666. Below you can see the block with #666f5b color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #666f5b to the mixer and play with it.