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.
