Prefacto - Prime Numbers9.0 - App Store

Discover the power of prime numbers with Prefacto!

Prefacto is your go-to app for everything related to prime numbers. Whether you're a math enthusiast, a student, or just curious, this app provides a comprehensive set of tools-all without requiring an internet connection.

FEATURES:

- PRIME NUMBER VERIFICATION: Instantly check if any number is prime.
- PRIME RANGE LISTING: Generate a list of prime numbers within any specified range.
- PRIME FACTORIZATION: Break down any number into its prime factors quickly and efficiently.
- GENERATE CUSTOM RANDOM PRIME NUMBERS: Create random prime numbers with customizable digits, up to 20 digits.
- SPEED TEST: Find out which phone is the fastest between your friends by racing up to 100 million.
- SAVE & SHARE RESULTS: Easily save or share your findings with others.

WHY PREFACTO?

- OFFLINE FUNCTIONALITY: Enjoy full functionality without needing an internet connection.
- LIGHTWEIGHT: Designed to be efficient and avoid taking up significant storage space on your device.
- SPEED: Experience fast calculations and instant results.
- MAXIMUM POWER: Check the **highest** numbers of **any** other app, thanks to advanced algorithms.

Dive into the fascinating world of prime numbers with Prefacto. Download now and start exploring!

Version History Updated for iOS 27 9.0 Sep 16 Minor improvements 8.22 Jan 8 Minor improvements 8.21 10/10/2025 Accessibility improvements 8.20 07/30/2025 Speed test your phone with your friends, now up to 100 million. 8.19 07/27/2025 You can now customize the app icon to be light, dark, or tinted (the app will automatically following your iOS settings)

This update includes lots of bug fixes and performance enhancements. If you ever want to abort a long operation, simply quit the app — and relaunch it to continue using it. 8.18 07/24/2025 8.12: NEW: Find out which phone is the fastest between your friends by racing up to 10 million.

8.14: This update greatly improves the speed test. 8.14 07/15/2025 NEW: Find out which phone is the fastest between your friends by racing up to 10 million. 8.12 07/15/2025 Improvements 8.11 06/06/2025 Fix chess set link 8.10 06/02/2025 Add link to chess set 8.9 05/30/2025 Add donate button 8.8 05/06/2025 Minor improvements 8.7 04/03/2025 This update:
- Makes it easier to see if the app is calculating or is done (though it usually does it so quick, you can't tell anyway)
- Opens the keyboard more smoothly across all pages in the app
- Remembers your last selection for digits amount in Randomize - including when generating random primes using Siri Shortcuts

Enjoying Prefacto? Please consider leaving a 5-star review!

- Stay Prime 8.6 03/20/2025 Minor enhancements

Love the app? Please consider leaving a 5-star review! 8.5 02/06/2025 Minor enhancements 8.4 01/17/2025 Minor design enhancements 8.3 10/28/2024 App now supports light and dark app icons on iOS 18. 8.2 10/14/2024 Improved handling of edge cases such as 0, 1, negatives, and decimals. 8.1 09/25/2024 Enjoy Prefacto on your new iPhone 16! 8.0 09/17/2024 This update improves the formatting of shared "List" results 7.60 08/16/2024 - Minor improvements to pave the way!
- Did you know? 2027 is a prime number. Only a few years away!
- Have some feedback? Write away!
- Enjoying the app? Please consider leaving a 5-star review - it would make my day!
- That all rhymed - hope that's OK! 7.59 06/06/2024 Enjoy Prefacto on your new M4 iPad! 7.57 05/23/2024 Updated app icon 7.56 03/17/2024 Minor enhancements 7.55 03/15/2024