I have a bunch of ones and twos that I know are more-or-less worth face value, but one of the $1 bills stands out. It looks like all of the other bills, from 1967 except instead of a serial number, 1867 1967 is printed in red in the two places where the serial numbers are normally located. Does this mean it's not a real bill? Or is something rare? I'm assuming the former but woudl appreciate advice if anyone knows.
PS It's quite creased - it has definitely been circulated.