Hex #157e8e or rgb(21,126,142) in RGB space is the tint of bluish cian. It has hue angle of 187.93 degrees, value = 56 and saturation = 85. #157e8e can be obtained by mixing 4 colors: 1 drop of blue, 5 drops of cyan, 1 drop of white, 5 drops of black.
Nearest safe hex - #006699. Below you can see the block with #157e8e color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #157e8e to the mixer and play with it.