This small size application is a free version of the famous Jigsaw Puzzle game and it has only the basic features such as creating a puzzle image from a picture, selecting the number of pieces (which is limited from 30 up to 1321 pieces) and removing option. You can select the color and the texture for your background too.
The Prime Number Spiral (a.k.a. the Ulam Spiral) is formed by marking the prime numbers in a spiral arrangement of the natural numbers. This is software is for exploring the Prime Number Spiral.
Factorizer may be used: (1) to get the prime decomposition of all numbers in a range of numbers (2) to get all factors of a single number or all factors of all numbers in a range (3) to find only the prime numbers in a range of numbers (4) to find pairs of prime numbers (e.g. 107 and 109) in a certain range (5) to count (without displaying) the prime numbers in a range of numbers (6) to find Fermat and Mersenne primes < 2,147,483,647
CFB Primes is an optimised PalmOS program which can find the prime factors and closest primes of any integer number up to one billion (US) in a few seconds or less. The standard edit menu allows you to make use of the results in other applications. CFB Primes is available free of charge.