IRS Number 1: 720-650-1165
Flagged on Whitepages : https://www.whitepages.com/phone/1-720-650-1165
IRS Number 2: 202-855-7335
https://www.whitepages.com/phone/1-202-855-7335
They have been a lot of fun to mess with this morning. 
Found another.
IRS Scammer number 3: 973-996-1162
https://www.whitepages.com/phone/1-973-996-1162
I did a quick search for this number on the forum and it turned out to be a tech support scam number previously. Now it's IRS.
They want me to pay $3966 by putting on a condom and going to the sex store.
Lol, these dumbasses kept transferring me to potential victims. At least I kept at least 5-6 people from getting scammed.
The folks at the 973 area code number above are easily amused. They asked me to play the “Drama” sound bite from the FireRTC soundboard along with the “Scream” and they were laughing their fool heads off for about 5 minutes. Yes, my methods are stupid, but if it keeps them off the phones for that long numerous times, I feel like I did my good deed for the day!
I got connected to another person who was calling. They also got the number from this site.
Looks like the 202-855-7335 number is rejecting calls from Fire RTC as I called from a landline with a generic number and they answered right away.