There ain’t nun older than her.

Sister Francis Dominici Piscatella, the world’s oldest nun at 112, has four words of advice for anyone who wants to match her longevity

“Teach until you die,” Piscatella, who celebrated her birthday in late April, told The Post.

Piscatella, in her 94th year of serving the Catholic Church, resides on Long Island’s South Shore, relishing her golden years. She advises people to emulate the kindness they have witnessed from their loved ones.

“You have to be a saint before you get to heaven.”

Now living in Amityville’s Queen of the Rosary Motherhouse, Piscatella had a long journey of faith and fate throughout her years.

Despite her age, Piscatella remains active and sprightly, stating, “For some reason, God is not ready for me to leave yet.” She reflects on her life, saying, “I feel ordinary. Age never occupied my thoughts; it merely happened.”

At the age of 2, while living in Central Islip, she experienced a life-changing event when she lost her left forearm in an accident involving a passing train. Nevertheless, Piscatella embraced this adversity and made the best of the situation.

“I was the second oldest of seven children. My mother wouldn’t let them help me because ‘you’re not always going to have your sisters, so you better just shape up and do things for yourself,’” she said.

“That’s what I did. Nobody really ever had to help with anything,” the centenarian added.

A blessed life

Growing up in a large family of Italian immigrants, the calling to Catholicism came from the love she saw her family extend to the family and community.

Her father, a foreman with the Long Island Railroad, brought daily sandwiches his wife made for a worker who showed up routinely empty-handed at lunch, and her mother was known to frequently cook “a big Italian meal” for the nuns in town.

Growing up in that environment, it became an easy call for Piscatella to join the order right out of high school, she said.

“It was normal for me to help people, and I liked helping them,” the super senior said.

However, finding a convent that would accept her with only one arm in 1931 proved challenging, and Piscatella had to physically show that her disability would not be a hindrance to service.

She only found her way into the Dominicans thanks to another nun seeking a change of scenery and leaving a teaching position in the void.

“The priest said, ‘Well, can she teach?’ And the sister said, ‘Oh, she’s a great teacher,” said Sister Francis Kammer, Piscatella’s close friend, former student and roommate for 45 years.

“And he said, ‘Then she stays.’ And she never looked back.”

Piscatella taught from her heart on all sorts of subjects, from math to history and arithmetic, while working in administrative roles since that fateful day at age 17 — until she was 84.

“Well, I don’t want to brag, but I was a pretty good student in everything. I was a good teacher because I was teaching myself too. I was knocking it into my own head,” said Piscatella, who spent much of her tenure at Dominican Commercial High School in Queens and Molloy College in Rockville Center, along with several New York City schools.

Nowadays, Piscatella enjoys deep prayer and connection with God while setting an example that’s being adored by the Catholic community on Long Island — many of whom she celebrated turning 112 with.

“She accepts the will of God. Her whole life, I never heard her complain about anything,” Kammer said.

“She had a brain bleed 11 years ago, and they thought she was never going to walk again and never going to talk again. She accepted it, and here she is walking and talking.”

Piscatella — said she is happy she “can still think” at her advanced age.

“I could still teach, or at least I think so,” Piscatella said.