Wiping the info, wipes the data inputted by your friend, it does not affect the phone's ability to be unlocked.
Secondly, its a GSM phone, therefore uses SIM cards. Using a different sim card with a different number is entirely possible. As the phone isnt locked to a number.
"That's it then. Cancel the kitchen scraps for lepers and orphans, no more merciful beheadings... and call off Christmas."