Hex #129598 or rgb(18,149,152) in RGB space is the tint of cyan. It has hue angle of 181.34 degrees, value = 60 and saturation = 88. #129598 can be obtained by mixing 4 colors: 1 drop of red, 5 drops of blue, 5 drops of cyan, 3 drops of green.
Nearest safe hex - #009999. Below you can see the block with #129598 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #129598 to the mixer and play with it.