You can't just go by the first number. Here's a search I did on the number below your message.

America Online, Inc. (NETBLK-AOL-MTC)

10600 Infantry Ridge Road

Manassas, VA 20109

US

Netname: AOL-MTC

Netblock: 64.12.0.0 - 64.12.255.255

So that means 64.12.0 thru 255. 0 thru 255

Every 64.12 with 65025 combinations following, are AOL addresses.

This message comes from Prodigy, and the same will match whatever number comes up. With the first two and 65025 possible combinations, reserved for Prodigy.