Number properties app

This app’s main functionality is to provide some elementary number analysis tools; it has been developed as an exercise in using some key Android functionalities such as AsyncTasks and multi-threading; this allows for a far better performance when it comes to big number crunching (a 15 digits number is found to be a prime number in less than 17 seconds on a Samsung Galaxy SII), and, more importantly, the UI remains responsive when this is happening.
We will be adding more features to this app in the next few months, so watch out for updates!

Key functionalities:

  • integer analysis: find the properties of an integer up to 15 digits (can be typed or random), for instance:
    • check to see if it is a prime/semiprime/sphenic/Niven/Woodall/Cullen/etc number;
    • list its prime factors;
    • list its proper divisors;
  • prime numbers list generation: generate prime numbers up to a given limit using the sieve of Eratosthenes
  • NEW FEATURE: Ulam’s Spiral!
  • decimal to fraction conversion: generate the corresponding fraction to any decimal number as you type it!


App icon
Number properties app - launch icon

Launch icon

Home page
Home page

Home page

Number properties app - Number analysis result

Number analysis result

Prime number found
Number properties app - Prime number found

Prime number found

List prime numbers
Number properties app - List prime numbers

List prime numbers

Ulam’s Spiral
Ulam's Spiral centred on 1

Ulam's Spiral centred on 1