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New Largest Known Prime Number Has More Than 23 Million Digits

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. 

How Your Job Can Predict Whether Or Not You’ll Get Divorced

These days, divorce is actually on the wane—2016 marked a nearly 40-year low in U.S. divorces—but whether or not you and your beloved spouse eventually part ways isn’t entirely up to fate. While individual relationships are all unique, statistically, there are demographic and other factors that influence whether or not a couple will divorce, from no-brainers like whether or not you’re willing to share chores equitably to more subtle factors like whether one partner smokes.

Your job matters too, as statistician Nathan Yau found in his analysis of 2015 data from the Census Bureau’s 5-year American Community Survey. As Business Insider and Entrepreneur report, the data shows that there can be vastly different divorce statistics when you’re talking about the marriages of bartenders and those of physical therapists, for instance.

A graph shows blue clusters plotting the links between income levels and divorce rates in different jobs.
Nathan Yau // Flowing Data

That doesn’t mean that going to work in a physical therapy office somehow better equips you for marriage than tending bar. Higher incomes and education levels, both intimately tied to your job, are also correlated with lower divorce rates. Sure, maybe the fact that flight attendants have to be away from their families for their job plays into their high divorce rates, but perhaps the type of person who wants to be a flight attendant might also be less inclined to settle down compared to people who dream of being an actuary.

Where does your job fall? Here are 10 fields with the lowest divorce rates surveyed:

1. Actuaries: 17 percent
2. Physical scientists: 18.9 percent
3. Medical and life scientists: 19.6 percent
4. Clergy: 19.8 percent
5. Software developers, applications and systems software: 20.3 percent
6. Physical therapists: 20.7 percent
7. Optometrists: 20.8 percent
8. Chemical engineers: 21.1 percent
9. Directors of religious activities and education: 21.3 percent
10. Physicians and surgeons: 21.8 percent

And here are the 10 highest-divorcing industries:

1. Gaming managers: 52.9 percent
2. Bartenders: 52.7 percent
3. Flight attendants: 50.5 percent
4. Gaming services workers: 50.3 percent
5. Rolling machine setters, operators, and tenders, metal and plastic: 50.1 percent
6. Switchboard operators: 49.7 percent
7. Extruding and drawing machine setters, operators, and tenders, metal and plastic: 49.6 percent
8. Telemarketers: 49.2 percent
9. Textile knitting and weaving machine operators: 48.9 percent
10. Extruding, forming, pressing, and compacting machine setters, operators, and tenders: 48.8 percent

Explore the data further on Flowing Data.

[h/t Business Insider]


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