Hex #66a91a or rgb(102,169,26) in RGB space is the tint of olive. It has hue angle of 88.11 degrees, value = 66 and saturation = 85. #66a91a can be obtained by mixing 4 colors: 3 drops of yellow, 4 drops of green, 1 drop of white, 2 drops of black.
Nearest safe hex - #669933. Below you can see the block with #66a91a color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #66a91a to the mixer and play with it.