Hoping to get their first win of the year, the Titans traveled to the RCA Dome for Week 5, as they played an AFC South match-up with the Indianapolis Colts.  The Titans got off to a surprising start, as QB Vince Young ran 19 yards for a touchdown.  Tennessee would follow it up in the second quarter, as kicker Rob Bironas kicked a 22-yard field goal to give the Titans a 10-0 halftime lead.  In the third quarter, Tennessee would get an unpleasant wake-up call, as Colts QB Peyton Manning completed a 13-yard TD pass to WR Marvin Harrison.  The Titans would get another field goal, as Bironas kicked a 47-yard field goal.  Unfortunately, Tennessee remained winless on the year, as Manning completed a 2-yard TD pass to WR Reggie Wayne in the fourth quarter.  With their loss, the Titans continued to stay at the bottom of the AFC South.  With the loss, the Titans dropped to 0-5.
Question: How many yards was the longest passing touchdown?
Answer: 13