Hex #88939f or rgb(136,147,159) in RGB space is the tint of blue. It has hue angle of 211.30 degrees, value = 62 and saturation = 14. #88939f can be obtained by mixing 4 colors: 5 drops of magenta, 3 drops of cyan, 4 drops of green, 3 drops of white.
Nearest safe hex - #999999. Below you can see the block with #88939f color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #88939f to the mixer and play with it.