Hex #667e5b or rgb(102,126,91) in RGB space is the tint of grass green. It has hue angle of 101.14 degrees, value = 49 and saturation = 28. #667e5b can be obtained by mixing 4 colors: 4 drops of yellow, 2 drops of magenta, 4 drops of cyan, 5 drops of black.
Nearest safe hex - #666666. Below you can see the block with #667e5b color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #667e5b to the mixer and play with it.