New Largest Known Prime Number Has More Than 23 Million Digits

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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. 

Millennials Get Blamed for a Lot, But They Could Help to Save the U.S. Postal Service

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Millennials get a bad rap for destroying everything from homeownership rates to fabric softener sales, but there's one important traditional industry they're enthusiastic about: the U.S. Postal Service. According to CityLab, a new USPS report [PDF] finds that young people's appreciation for snail mail could help boost the often-struggling agency's fortunes in the future.

Probing for insights into the minds of young people ages 18 to 34 (a little off from the Pew Research Center's definition of Millennials as being people ages 22 to 37), the USPS conducted surveys and hosted live chats online to figure out what Millennials think of the agency, and how the Postal Service can ignite their love of snail mail.

That's vital, because as it is, technological innovations like email and online bill payments are putting the USPS out of business. It lost money for the 11th year in a row in 2017, and while shipping packages is getting more popular (thank you, online shopping habits), it hasn't been enough to offset the decline of mail during that year—mail rates declined by 50 billion pieces in 2017. Young people ages 18 to 34 received an average of 17 pieces of mail each week in 2001, while they only receive 10 now.

But Millennials, it turns out, love mail, even if they don't want to pay their bills with it. As the report observes, "many Millennials still delight in receiving personalized notes or cards around holidays, birthdays, and other special occasions." Three-quarters of respondents said that getting personalized mail from friends and family "makes them feel special." According to the report, around 80 percent of Millennials say they're satisfied with the USPS, around the same rate as older, stamp-loving generations. More Millennials than Boomers, meanwhile, have a USPS.com account, and 59 percent say that the USPS is an innovative organization.

Millennials mentioned several ideas for USPS improvements that already basically exist, like self-service kiosks, at-home package pickup, and Informed Delivery emails, meaning the Postal Service isn't always the best at getting the word out about the cool things it already does. The report also shows that the Postal Service is still working on an augmented reality service that could give you a look at what's inside a package before you open it. (The idea debuted in 2016, but the app was largely limited to showing animated messages.)

The surveys and discussions did come up with a new idea to endear the post office to Millennials: a rewards program. The young people surveyed suggested that members could earn points by buying stamps or mailing packages and use them to redeem discounts or enter contests.

Millennials: They may be ruining vacations, but at least they're ready to save the mail.

[h/t CityLab]

And the Most Miserable State in America Is …

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Where you live has a huge impact on your health and happiness: Location dictates everything from your local weather to crime rates. Each year, the Gallup-Sharecare Well-Being Index interviews 160,000 U.S. adults about their lives, scoring different regions of the country on their residents' well-being and ranking the states based on the overall happiness of the people who live there. This year, according to USA Today, 24/7 Wall Street decided to add to that dataset by analyzing even more socioeconomic data from the U.S. Census Bureau, the FBI, and elsewhere, such as poverty rates, crime, social ties, and health across the U.S. The result is a more complete picture of how happy some states are, and how miserable others are.

Some of the rankings might surprise you. Both Dakotas made it into the top 10, with South Dakota taking the overall prize for the happiest state. In the survey, residents reported a high sense of purpose, saying they like what they do each day and have reached most of their goals in the last year. More than 80 percent of respondents said they like what they do daily, more than any other state. In other high-scoring states, residents report a strong sense of security, good public health, and strong social ties. (Low crime and unemployment rates help.)

Here are the 10 happiest states in the U.S., according to the rankings.

1. South Dakota
2. Vermont
3. Hawaii
4. Minnesota
5. North Dakota
6. Colorado
7. New Hampshire
8. Idaho
9. Utah
10. Montana

Meanwhile, economic concerns and high crime dominate the responses within the rankings of the most miserable states in the U.S. West Virginia, the least happy state on the list, is plagued by financial insecurity and poor health outcomes. In the survey, West Virginians had the lowest numbers of people who said they were in "near perfect" physical health, liked what they do every day, or have strong social ties. Other states in the top 10 list of least happy states include Louisiana and Arkansas, both of which have some of the highest rates of poverty and violent crime in the country. In Oklahoma, one out of five people who responded to the survey said they struggled to afford food, and in Kentucky, 23 percent of respondents said they have been depressed in their lifetime.

These are the 10 most miserable states, according to these calculations.

1. West Virginia
2. Louisiana
3. Arkansas
4. Mississippi
5. Oklahoma
6. Kentucky
7. Ohio
8. Nevada
9. Indiana
10. Rhode Island

Head to USA Today to see the full list.

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