Got a call from this number I didn't recognize so I didn't answer it.  No message left, so I waited a while then called it back from a blocked number.  Almost immediately I got the 3 standard disconnect tones, followed by the message that the number I dialed, 213-966-0005, had been disconnected / no longer in service.  Interesting, since that's not the number I dialed  Perhaps even more interesting is the fact that when I hung up and called it back because I realized I forgot to grab the 213 number, it came up as busy.  I did this a few more times and confirmed that each time the pre-recorded disconnect message was playing, I'd get a busy signal until it finished.  Sounds more like an answering machine than a telephone disconnect message which is indicative of something shady.  Very likely a spammy or fraudulent caller.  Blocked, naturally.