Let’s find out the most enormous known prime number using java

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According to Wikipedia, the biggest known prime number (as of December 2020) is 2^82,589,933 − 1, which has 24,862,048 digits when printed in base 10.

The number itself is unfathomable.

Let’s write a java program that calculates this number and writes it in a text file.


It doesn’t take much time to calculate the number, but writing on file or flushing on Standard output would take quite a significant time.

The file is quite large: 24.9 MB. Any text editor would struggle to open it.

Here is a glimpse of the number:


If you want to see this on yourself then this file: theLargestKnownPrime

for copy/paste pleasure: https://github.com/rokon12/100DaysOfJava/blob/main/src/main/java/com/bazlur/Day013.java


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Author: A N M Bazlur Rahman

Java Champion | Software Engineer | JUG Leader | Book Author | InfoQ & Foojay.IO Editor | Jakarta EE Ambassadors| Helping Java Developers to improve their coding & collaboration skills so that they can meet great people & collaborate

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