Hex #55919c or rgb(85,145,156) in RGB space is the tint of bluish cian. It has hue angle of 189.30 degrees, value = 61 and saturation = 46. #55919c can be obtained by mixing 4 colors: 5 drops of blue, 2 drops of green, 4 drops of white, 1 drop of black.
Nearest safe hex - #669999. Below you can see the block with #55919c color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #55919c to the mixer and play with it.