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Here it comes, the Inconceivable Prime Number

I learned today that the largest prime number ever discovered was discovered recently. A prime number is an integer that is not -1, 0, or 1, and has no factors other than itself and 1. Examples are 2, 3, 5, 7, and 97. The newly discovered prime number is 2^20,996,011 - 1. This means multiply 2 by itself 20,996,001 times and subtract 1. The result has 6,320,430 digits. This is getting to be really huge.

When I was a child, I learned about prime numbers such as 2¹²⁷ - 1, which can fit on a single line of print, as being the biggest. This is a scientific number. If you click on that link, you get my classification of numbers into six categories: counting, statistical, scientific, literary, inconceivable, and indescribable. In addition, I subdivide literary numbers into poem numbers, novel numbers, and encyclopedia numbers. As I grew older, the largest prime number became a poem number, and once computers got into the act, the largest prime quickly became a novel number. The prime that was discovered today is on the verge of becoming an encyclopedia number, which means, printed out, it could fit a small encyclopedia.

The number was discovered by 200,000 or so computers acting in parallel. Many people have connected their computers to a site that computes these numbers, using the people's own computer to do the computations. The technique has been used before to discover what would be much more earth-shaking, namely extraterrestrial Life, by analyzing the data from Aricebo.

As computers get better and faster, and more and more people are willing to get involved, the day may come when the largest prime number will be inconceivable. When that happens, they can't print it out or count it out; there is not enough time in a lifetime to do it. This happens when it exceeds 20 billion digits. So here it comes! The Inconceivable Prime Number.