Margaret Loughrey, from Strabane, was found dead on Thursday morning.
Her death is not being treated as suspicious.
Her life was transformed by the 2013 lottery win – at the time it was the largest ever jackpot won in the North of Ireland.
Police confirmed officers attended the scene and said a post-mortem examination would take place.
Local councillor Paul Gallagher, a neighbour, said: “People are shocked today.”
A PSNI spokesman said: “Police received a report of the sudden death of a woman at the Ballycolman Lane area of Strabane on Thursday September 2.
“A post-mortem is due to take place but at this stage, the death is not being treated as suspicious.”
The NI Ambulance Service confirmed they attended the scene on Thursday morning.
A NIAS spokesman said: “We were called to an emergency in the Ballycolman area of Strabane at 10.30am this morning. No patients were taken from the scene.”
Ms Loughrey, who was aged in her 50s, matched five numbers and two lucky stars in the draw in November 2013.
In total, she scooped £26,863,588.
In an interview at the time, she said that on the day she bought the ticket, she had been to the job market to get an application form for a job with a charity.
“Got up on Wednesday morning, checked the ticket, just had a notion, checked the ticket and that was it – five numbers, two stars, happy days,” she told the BBC in 2013.
“I never panicked. I’m level-headed and I know I’ll think it all through and do the right thing, see to the right people.
“It’s in my name at the minute, it’s £27m, it’s not going to be mine, it’s going to be spread around.
“No point having £27m and being lonely. That can’t make me happy, that can only make me happy that everybody else’s happy and so far everybody is absolutely delighted.”
Despite her new-found wealth, becoming one of Ireland’s richest people overnight, she continued to live in her home town – and was never far from the headlines.
In 2014 she purchased the derelict site of Herdmans Mill in Sion Mills for around £1m. While it was reported that she had ambitious plans to revamp the property, these never came to fruition.
The same year, she became embroiled in a row with Sion Mills Cricket Club, founded by the Herdman family in 1864, after locking them out of their pitch on the 60-acre grounds.
The team was subsequently forced to forfeit two home games for the first time in their 150-year history, ruining hopes that local ownership of the ground would secure its future.
Ms Loughrey later came to an agreement with the cricket club to allow it to use the pitch again.
In 2015 Ms Loughrey was ordered to do 150 hours of community service after being convicted of assaulting a taxi driver.
In 2018 she was ordered to pay £30,000 to a former employee for bullying and firing him on a “vindictive whim”, after losing an employment tribunal.
In an interview in 2019, Ms Loughrey said her lotto win had “sent her to hell and back”, even though she was unemployed and living on benefits when it happened.
“Money has brought me nothing but grief. It has destroyed my life,” she said.
“I have had six years of this. I don’t believe in religion, but if there is a hell, I have been in it.
“It has been that bad.
“I went down to five-and-a-half stone.”Tags: