It’s the gift that keeps on giving — whether he likes it or not!

A New Jersey dad’s two prankster sons hung a billboard on a busy Atlantic City highway, complete with their old man’s cellphone number and a message urging strangers to call and wish him happy birthday, according to a report.

Chris Ferry, of Linwood, who turns 62 on Saturday, has been flooded with about 10,000 calls and text messages — from well-wishers, nostalgics and oversharers — in less than a week, he told KYW News Radio.

“They get me on the phone, they want to talk to me, they want to tell me about their most memorable birthday,” he told the station. “People say, ‘I lost my dad last year.’ I had one guy tell me, ‘I tried to call my father to tell him about the billboard and he didn’t pick up, so I figured I would call you to talk to you and now you’re not picking up.’”

He’s getting a kick out of the gesture — even though it has effectively hijacked his smartphone, he said.

“I really haven’t been able to use my phone in a normal way,” he said. “There’s a call coming through right now, it’s happened like three times since I’ve been on the phone with you.”

But he added, “I got the joke. It was funny, it was good. And then I thought, ‘Man, I’m going to be getting a lot of phone calls.'”

The billboard went up on the Black Horse Pike last week, proclaiming, “Wish My Dad Happy Birthday. Love, Your Sons” next to a giant image of Ferry’s face.

His son Christopher Ferry Jr., of Florida, said he wanted to do something funny and special for his pop’s birthday.

“We wanted it to be a birthday for him to remember,” he said, adding he’s been pranking Dad since he was a kid.

“He’s laughing,” said Ferry Jr. “He’s trying to answer as many texts as he can, he’s answering phone calls. He’s actually really getting a kick out of it.”

The soon-to-be birthday boy’s voicemail was full when The Post called Monday. But he told the radio station, “It’s been really good-natured fun — although at my expense.”