# Windows software to find all factors of numbers,

prime numbers and pairs of primes (and more)

## 1. Introduction

*Factorizer* may be used to:
- get the prime decomposition (a.k.a. prime factorization) of all numbers in a range of numbers up to 2,147,483,646,
- get all factors (prime and non-prime) of a single number, or all factors of all numbers in a range,
- find only the prime numbers in a range of numbers,
- find pairs of prime numbers (e.g. 107 and 109) in a certain range,
- count (without displaying) the prime numbers in a range of numbers.
- find Fermat primes and Mersenne primes < 2,147,483,647
- find the "Palmen color" of a number or the colors of a range of numbers.

In addition a "filter" condition may be set to allow examination of numbers with a constant offset from an arithmetical or a geometrical progression, e.g., just those numbers of the form 7*n - 12 or 10^{n} + 2. Here is a typical screenshot:

The text in the output window can be edited, so you can remove unwanted output and add your own comments before copying to the clipboard for transfer to another program such as a text editor.

Examples of the use of the program are given below, first without a filter condition in effect, then with various filters in effect.

Following accepted mathematical convention, the number 1 is not held to be a prime number.

The remainder of the user manual is in the following sections:

**How to obtain the software:** A fully-functional version of the *Factorizer* software is available for free download from this website. Click on the following link to go to a web page with further information:

**Download ***Factorizer* ...