When I got on the phone with Bob Newhart earlier this month, the first thing I told him was that he’s the same age as my father who, like Newhart, was also an accountant and also served during the Korean War.

The comic legend paused a moment and replied: “Well, hello son.”

The 89-year-old Oak Park, Ill., native has acted as a sort of surrogate father for several generations of fans during his decades-long career that includes starring roles in “The Bob Newhart Show” and “Newhart.” He’ll be in Minneapolis to perform on June 28 as part of the inaugural Minneapolis Comedy Festival, which kicks off Monday.

Newhart entered the business through an unusual side door and landed a record deal before performing live stand-up comedy anywhere. But his first post-war gig was as an accountant.

“I was not a very good one and not a very happy one,” he explained. “One of my duties was being in charge of petty cash. Salesmen would give me receipts, I’d give them cash, and at the end of the day, I had to balance what was left in the cash drawer against the receipts. It never balanced.

“I said, ‘I don’t think I’m cut out for accounting.’ I was single, living at home in Chicago. But everyone was always telling me I’m funny. And I just decided to try it and devote a year to it. A year became two and then two became three.”

Newhart found a day job as an advertising copywriter and befriended a co-worker who enjoyed spinning absurd scenarios with Newhart over the phone. They began recording the calls and when his co-worker decided to focus on his paying job, Newhart continued developing the routines on his own.

A Chicago radio DJ liked Newhart’s tapes and forwarded them to the then-new Warner Bros. Records. The label signed him in 1959.

“They liked what I was doing, or said they liked it, anyway. They said, ‘We’ll record your next nightclub show.’ And I said, ‘Well, we have a problem there. I’ve never played a nightclub.’”

Still, the label offered to find a club for Newhart and, a few months later, he was on a stage in Houston, performing his one-sided telephone call routines in front of a live audience. “The Button-Down Mind of Bob Newhart” landed in stores in May 1960. And the first market Newhart found a following was Minneapolis.

“The label told me it was going crazy and every pressing they had they were sending to Minneapolis. Several of the local DJs at the time would announce that, say, (the sketch) ‘Driving Instructor’ was going to be on at 7 and 9:30 and people would tune in.”

Young people discovered Newhart first. “It started with college audiences. There was a sea change in comedy at the time. You had Mike (Nichols) and Elaine (May), Lenny Bruce, Mort Sahl, myself. That’s what they wanted, a totally different kind of humor. And they couldn’t afford to go to nightclubs, but they’d buy comedy records, sit around in a dorm and drink beer and listen. That was their nightclub.”

That summer, “The Button-Down Mind of Bob Newhart” started to make an impact nationally as Newhart was performing in clubs when he could.

“I was playing Minneapolis in what would have probably been June when I got a call to do the Emmy Awards in 1960. That kind of exploded the record. Suddenly I was getting on all the (television) shows. I’d get a call: ‘Do you want to do Ed Sullivan six nights or do you want to do eight nights?’

“I was totally unprepared for what followed. It was like New Year’s Eve every night. I was just kind of swept along by it. It had a life of its own.”

“The Button-Down Mind of Bob Newhart” went on to become the first comedy album ever to top the Billboard charts. When the follow-up, “The Button-Down Mind Strikes Back,” hit racks later in 1960, it spent eight straight months at No. 2, behind “Button-Down Mind,” which won album of the year at the 1961 Grammy Awards. Newhart was also named best new artist, the only time a comedian picked up that title.

With America now smitten by Newhart’s droll sense of humor and deadpan delivery, he found ample work on television, in films and on the road. Critics and audiences embraced both “The Bob Newhart Show” (1972-1978) and “Newhart” (1982-1990), and while he slowed down his career after “Newhart,” he has never retired.

“I’ve cut way back (on stand-up),” he said. “This year, I’ll probably do five or six shows, where I used to do 20 or 30. The travel is tough with airplanes and canceled flights and hotel rooms. I’ve stayed in palatial, beautiful rooms in great hotels, but it’s not home. It takes its toll after a while. But I still enjoy doing it because I’m proud of the fact I can still do it, that the mind is still supple enough to be able to do it.”

Newhart hosted “Saturday Night Live” in 1980 and 1995. Might he pull a Betty White and do it once more?

“Oh God, no, I could never do that again,” he said with a chuckle. “The process is tough. They give you maybe 20 sketches and then you rehearse and they start dropping them until you’re down to maybe six or eight. You never have a chance to learn a sketch because it could be pulled the night of the show. Everybody reads from the cue cards because you have to. It’s an art form to make it look like you’re not reading cue cards. That’s for young people, not someone who is about to be 90.”

Speaking of turning 90, Newhart will do just that in September. Any big plans?

“You know, there was some talk about doing a stand-up appearance in Chicago, my hometown. But I thought, well, you know, because of my accounting background, generally speaking, you only reach 90 once. There’s no second 90. I don’t want to do stand-up, I want to be with my family.”

Over the past decade, Newhart has remained in the public eye thanks to a recurring role on “The Big Bang Theory” and its spin-off “Young Sheldon.” Does he ever watch any of his old shows?

“I don’t look for it, no,” he said. “But if I happen to have the TV on and see one, very often I’ll have no recollection of it. I know I’m in it, I can see me in it, but I have no idea how it ends. So I’ll sit down and watch it like any other viewer.

“But I don’t watch that much TV and I don’t watch sitcoms that much. All together, I guess I’ve done maybe 20 years of television. I kind of know where the joke is going to go.”

The Minneapolis Comedy Festival

What: A new weeklong festival with 14 comedians, podcasters, YouTubers and comic actors performing in several downtown Minneapolis venues. See minneapoliscomedyfestival.com for further details. The lineup includes: