Ask HN: Pic of an MD5(?) tattoo, time to decode it

"My little brother (23 yrs old) recently got a code tattooed on his forearm (picture attached). He’s framing this tattoo to everyone in a very mysterious way, to the point of being arrogant. He hasn’t told anyone what it means and has challenged his Facebook friends to try to figure it out.

As an older brother, I’m obligated to rain on his parade.

$25 gift card (wherever you like) to the first person to figure it out."

The string, for your convenience: ce881618a0393cc3d6eba8d0e0fe9621