Hex #405a5b or rgb(64,90,91) in RGB space is the tint of cyan. It has hue angle of 182.22 degrees, value = 36 and saturation = 30. #405a5b can be obtained by mixing 4 colors: 4 drops of magenta, 3 drops of cyan, 4 drops of green, 5 drops of black.
Nearest safe hex - #336666. Below you can see the block with #405a5b color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #405a5b to the mixer and play with it.