New Largest Known Prime Number Has More Than 23 Million Digits

iStock
iStock

Prime numbers come in all sizes: They go down to single digits and grow infinitely larger. But calculating the exact quantity of the largest prime numbers in existence takes serious time and effort. Now, thanks to help from a volunteer and his computer, the Great Internet Mersenne Prime Search (GIMPS) has identified the newest largest prime number we know of.

The prime number has 23,249,425 digits, surpassing the previous record holder by 1 million digits. It can be written as 277,232,917-1 or M77232917. Like other prime numbers, the quantity can only be divided by one and itself. But unlike some smaller primes, this one joins a special category called Mersenne primes.

Mersenne primes are found by calculating numbers to the second power and subtracting the value of one from the total. Only 50 prime numbers have been found this way, and a lot of computing power is required to uncover them.

Since 1996, GIMPS has been crowdsourcing computers to discover larger and larger prime numbers. Anyone can download their program and dedicate their unused processing power to churning out algorithms in search of the next record breaker. Volunteers whose computers successfully identify a new prime number are eligible for a cash reward of up to $3000.

The most recent winner was Jonathon Pace, a 51-year-old electrical engineer from Tennessee. His computer calculated the number M77232917 on December 26, and its prime status was independently verified by four separate computers.

GIMPS is constantly outdoing itself, with the previous largest prime announced just two years ago. If you'd like to join the effort, their prime-hunting software is free to download. But don't expect instant results: Pace was volunteering with GIMPS for 14 years before his altruism paid off. 

Looking to Downsize? You Can Buy a 5-Room DIY Cabin on Amazon for Less Than $33,000

Five rooms of one's own.
Five rooms of one's own.
Allwood/Amazon

If you’ve already mastered DIY houses for birds and dogs, maybe it’s time you built one for yourself.

As Simplemost reports, there are a number of house kits that you can order on Amazon, and the Allwood Avalon Cabin Kit is one of the quaintest—and, at $32,990, most affordable—options. The 540-square-foot structure has enough space for a kitchen, a bathroom, a bedroom, and a sitting room—and there’s an additional 218-square-foot loft with the potential to be the coziest reading nook of all time.

You can opt for three larger rooms if you're willing to skip the kitchen and bathroom.Allwood/Amazon

The construction process might not be a great idea for someone who’s never picked up a hammer, but you don’t need an architectural degree to tackle it. Step-by-step instructions and all materials are included, so it’s a little like a high-level IKEA project. According to the Amazon listing, it takes two adults about a week to complete. Since the Nordic wood walls are reinforced with steel rods, the house can withstand winds up to 120 mph, and you can pay an extra $1000 to upgrade from double-glass windows and doors to triple-glass for added fortification.

Sadly, the cool ceiling lamp is not included.Allwood/Amazon

Though everything you need for the shell of the house comes in the kit, you will need to purchase whatever goes inside it: toilet, shower, sink, stove, insulation, and all other furnishings. You can also customize the blueprint to fit your own plans for the space; maybe, for example, you’re going to use the house as a small event venue, and you’d rather have two or three large, airy rooms and no kitchen or bedroom.

Intrigued? Find out more here.

[h/t Simplemost]

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Tenino, Washington, Is Loaning Residents Wooden Money to Boost Its Economy

Pixabay, Pexels
Pixabay, Pexels

Like many places around the country, Tenino, Washington, has taken a financial hit during the COVID-19 pandemic. Instead of writing checks to residents in need, the town is printing its own money on wood in an effort to boost the local economy, CNN reports.

Any Tenino resident living below the poverty line can apply for a wooden currency loan. To qualify, they must prove they lost money as a result of the pandemic, but as town mayor Wayne Fournier told The Hustle, “we’re pretty open to what that means.”

One wooden note is worth $25, and qualified candidates can receive up to 12 of them per month—the equivalent of $300. The dollars look unique, with a retro design and a Latin inscription that roughly translates to “We’ve got this handled.” But the special money serves a larger purpose: The notes are only valid at local businesses, which ensures spenders keep the cash within the local economy instead of giving it to major retailers. When a transaction has been made, business owners can take the currency to City Hall and exchange it for real U.S. currency.

This isn't Tenino's first time enduring economic hardship. By 1931, America had entered the Great Depression, and the town's local Citizens Bank had frozen all accounts. Tenino responded by printing its first run of wooden dollars that year. That original program, which was funded by the local Chamber of Commerce instead of the town government, allowed residents to exchange up to 25 percent of their bank deposits for the wooden notes.

Today the bills from the 1930s are collector's items. The town had that part of its history in mind when it launched its new alternative currency program; the wooden dollars circulating today were even printed using the same newspaper press used to make the wooden money 90 years ago.

[h/t CNN]