Hex #407e6b or rgb(64,126,107) in RGB space is the tint of greenish cian. It has hue angle of 161.61 degrees, value = 49 and saturation = 49. #407e6b can be obtained by mixing 3 colors: 2 drops of yellow, 5 drops of blue, 1 drop of green.
Nearest safe hex - #336666. Below you can see the block with #407e6b color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #407e6b to the mixer and play with it.