Even Barry Manilow can’t believe the year he’s experienced.

Whether he’s checking out a Stevie Nicks concert in Palm Springs, California, or dashing into a high-end retailer in Las Vegas, the recognizably factor is amplified.

“This crazy year,” Manilow says by phone from his California home, a hint of disbelief in his voice. “People always say the nicest things. All they want to tell me how much my music has meant to them and to have a selfie and I am happy to do it. They believed in me when I didn’t believe in me.”

Manilow’s resurgence – not that the maestro celebrating 50 years in the industry ever went anywhere – is threefold: A spring sold-out run at Radio City Music Hall (a homecoming of sorts for the Brooklyn native); a record-breaking residency at the Westgate Resort & Casino in Las Vegas with his ongoing “Barry Manilow – The Hits Come Home!” (he smashed Elvis Presley’s record of 636 shows at the venue’s International Theatre in September); and the 30-year dream of bringing his original musical “Harmony,” written with longtime collaborator Bruce Sussman, to Broadway (it opened Nov. 13).

Manilow, 80, will cap his year with “Barry Manilow’s A Very Barry Christmas,” a holiday special airing on NBC (10 p.m. ET/PT) Monday and streaming on Peacock the next day.

The music icon, who has sold more than 85 million records worldwide with eternally hummable hits including “Copacabana (At the Copa),” “Can’t Smile Without You,” “Looks Like We Made It” and “Mandy,” chatted about what makes a memorable Christmas song, why he loves his Las Vegas venue and his hopes for “Harmony.”

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Question: So what makes something “a very Barry Christmas?” Is it your mere presence?

Barry Manilow: (Laughs.) I’m sorry to say it is. I’d been doing this Christmas show (on the road) for about five years and I love it and the audience loves it. We changed the set around and we have snow and Christmas trees and the presents and it’s wonderful. When the curtain opens, it looks like a Christmas card. The NBC people came out to check out my regular show and in conversation they said they were looking for a Christmas show since the writers were on strike and I said, ‘I have a Christmas show ready to go!’ It’s a cut-down version of my 90-minute show but it’s the highlights – Christmas songs and some of mine that people love. When I did my first TV special (in 1977), there were probably five cameras. Now it’s 12 cameras! Holy moley! I went into the control room and it looked like they were launching the Space Shuttle. But it’s a beautiful-looking show and it sounds great.

You have a new cover of Mariah Carey’s “All I Want for Christmas is You,” which seems like an interesting choice for you. What made you want to cover it?

I was supposed to have a Christmas album out this year, but it takes me awhile because I have to arrange all the songs and one of the ones I wound up completing was the Mariah song. It’s a wonderful record and a solid song. When I dove into it I didn’t want to do the Wall of Sound Phil Spector thing she did, which is great sounding. The melody and the lyrics are strong, so I went the other way and made it much more simple. There are hardly any instruments playing and it builds and builds and by the time we get to the bridge it’s a really big record. When it came time to do something for this Christmas, I said to (manager and husband) Garry (Kief), put it on Spotify and see what happens and it started to blow up without any help. I never thought I’d be saying I have a record with a bullet, but what a way to end this insane year.

You’re a master at melody. What do you think makes a good Christmas song?

Something that makes you feel and a catchy melody are the top answers. You get a catchy melody, you can sing anything. But for me, I need to feel something. The ones we all know, it’s because you feel good or melancholy. Every new artist eventually makes their first Christmas album and it’s hard to write Christmas songs.

And what’s the status of that Christmas album you’ve been working on?

I’ll try again this summer to finish it. I’ve laid out all that I want to do with it.

So let’s talk about Vegas. I’ve seen you at various places there over the years, but what makes Westgate such a good fit for your show?

For me, it’s the perfect place. I like to communicate with an audience. The bigger the crowd gets, the more trouble I have communicating. This place, which is like 1,500 people, is the perfect place for what I want to do. I want to make people understand the words I’m saying. I want them to feel something when I’m on that stage. I did a run at the Paris (casino) and it was the most beautiful and expensive show we’ve ever done and a wonderful production. But it was so complicated that I could not change anything. If I wanted to throw another song in, it took a week to relight and restage and I didn’t realize I would be imprisoned. At the Westgate, I can throw in any song I want; they just redo the lights and we can throw it in the show that night.

Do you spend much time doing anything else in Vegas?

I do not. There’s always something to do for me in the afternoon, but the last thing I would do is to go out. I have gone shopping a few times because they have a big mall with some nice stores like Prada and this and that. This year has been one of the biggest of my career and my face is pretty well known at this point. I went to see Stevie Nicks and it was “Barry! Barry! Barry!” and that hasn’t happened like that in a while.

What did you think of Stevie?

I thought she was great. She’s got a very interesting-sounding voice and is very appealing. The big surprise was how much she talked between songs and described the songs she was going to do. I didn’t expect that. She made us all want to listen to the song that was coming up.

Over the years we’ve talked about “Harmony.” (Manilow’s musical based on the true story of arguably the first boy band from the 1920s and ‘30s – The Comedian Harmonists – superstars of their era based in Berlin.) It’s gone from San Diego to Atlanta to Los Angeles to Off-Broadway and now, finally Broadway. What is your overriding feeling of seeing that goal achieved?

Now we hope, and the big question is, will it last? No one can predict that. January and February are usually the worst months for Broadway, so if we can make it through that we might have a successful Broadway show. Right now we’re doing very well. It was an amazing day when the marquee went up. It made it real. Did it make me cry? No, but it felt like finally, after all these years.

You recently announced your last concerts in England coming up this summer. Have you thought about when you might stop performing in the U.S.?

I like working, I do. I’m still healthy and I still can sing and look pretty much the same. I don’t have any plans on stopping. I like being with the band and I enjoy standing on stage and talking to the audience. I wanted to stop those crazy tours in England because to make any money there you have to stay a couple weeks, so I’m saying goodbye to touring in England like we did in the U.S. We don’t tour anymore, but I’ll go out and do a few weeks. It was the touring that had to stop. I missed the dogs. I missed my life.

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