Hex #009188 or rgb(0,145,136) in RGB space is the tint of cyan. It has hue angle of 176.28 degrees, value = 57 and saturation = 100. #009188 can be obtained by mixing 4 colors: 1 drop of blue, 2 drops of cyan, 1 drop of green, 1 drop of black.
Nearest safe hex - #009999. Below you can see the block with #009188 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #009188 to the mixer and play with it.