Hex #178cc2 or rgb(23,140,194) in RGB space is the tint of bluish cian. It has hue angle of 198.95 degrees, value = 76 and saturation = 88. #178cc2 can be obtained by mixing 3 colors: 1 drop of red, 5 drops of blue, 5 drops of cyan.
Nearest safe hex - #0099cc. Below you can see the block with #178cc2 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #178cc2 to the mixer and play with it.