Sure it's easy. IF you are able without missing any kind of emergency, turn off the ringer or disconnect a landline. You can turn off or down a cell and get the same results, or use a blocking app. If you cannot, then a call blocker may be of assistance for a landline. The way to nail them is by giving them zilch from the numbers they call. If they've got nobody playing, they're out of business.
IRS? Hahaha. These people are getting better and better. IRS is going to hire some person that cant even pronounce IRS? I just called the number back and told them they are frauds and that i was going to report them. He insisted he was going to report me to the police... hahaha IRS reporting to police? Now thats quite exciting!
Know this people... IF IRS EVER HAS TO CONTACT YOU THEY WILL DO IT BY MAIL. IRS WILL NEVER CONTACT ANYONE VIA PHONE.
DO NOT PROVIDE ANY INFORMATION TO ANY ONE CALLING CLAIMING TO BE IRS. ITS BULL.