Hex #129d98 or rgb(18,157,152) in RGB space is the tint of cyan. It has hue angle of 177.84 degrees, value = 62 and saturation = 89. #129d98 can be obtained by mixing 4 colors: 1 drop of magenta, 4 drops of blue, 5 drops of cyan, 4 drops of green.
Nearest safe hex - #009999. Below you can see the block with #129d98 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #129d98 to the mixer and play with it.