See also:

• Computers: Computer Science: Distributed Computing: Projects: Cryptography  (15)
• Kids and Teens: School Time: Math: Counting and Numbers  (8)
• Science: Math: Number Theory  (1,216)

This category in other languages:
	French  (13)

• Absolutely Abnormal Numbers - Published as math.NT/0006089, this note investigates numbers that are normal to no base whatsoever, and writes down explicitly such a number.
• Arabic numerals - Describes the history of the Arabic numeral system that is in use nearly all over the world today.
• Ask Dr. Math: History of the Terms Google and Googleplex - Explains how these very large numbers (1 followed by a hundred zeroes, and 1 followed by a google of zeroes, respectively) were named. With links to references. From Swarthmore's Dr. Math.
• Catalan Number -- MathWorld - Illustration of the Catalan numbers related to Euler's polygon division problem.
• FAQ on Special Numbers - Answers to Frequently asked questions about special numbers.
• Fibonacci Numbers and the Golden section in Nature - Puzzles and things to do, for schools, teachers, colleges up to university level students, or just for recreation.
• Friedmann's S-Numbers - These are numbers where an expression can be given using the operations of addition and squaring, using the digits of a number in order, which gives the original number. Algorithms, theorems and results.
• Fun With Numbers - Includes some lists of numerals, relating to basic operations performed on certain constants. Not updated since 1995.
• The Golden Pentagon - MathPages depiction of tiling a plane using a progression of equilateral triangles dividing a pentagon. Most interesting is that this pentagon is uniquely and recursively divided by triangles, just as is seen in the more common recursive division of the Golden Rectangle.
• 37 Heaven - Collects information around the number thirty-seven.
• Indian numerals - Describes the history of the indian numeral system.
• Inverse Symbolic Calculator - A set of programs and specialized tables of mathematical constants dedicated to the identification of real numbers.
• Jewish Encyclopedia: Numbers and Numerals - Discusses the uses and symbolism of various numbers in Hebrew literature.
• Just Who is Mr. 666? - Uses gematria to calculate the number of the beast, and evaluates what it may mean w/r specific Hebrew words and names in the Bible adding up to 666.
• Mathemagic - In praise of the beauty of the numbers pi, e and phi.
• Mathematical Constants and Computation - Essays, references, links, software.
• Number Gossip - Numerous special categories of numbers, searchable.
• RJN's More Digits of Irrational Numbers - Several million digits of e, and the square roots of 2, 3, 5, 6, 7, 8, and 10.
• Square root of 2 - Provides information about the square root of 2, lists the first 1000 digits and provides links to pages with up to 5 million digits. Also contains download links for programming libraries for calculating numbers with high precision or many digits.
• Stewy's Site - The infinitesimal is the opposite of infinity, and mathematicians still argue over its existence. This page probes into one of the weirdest numbers in mathematics.
• Sum Beastliness - Some simple mathematics associated with 666, the Number of the Beast.
• Triangular Numbers - Properties of triangular numbers including reversible, happy, harshad, highly composite, deficient, abundant ones.
• Vampire Numbers - Numbers with a factorization containing the same digits, e.g. 1530 = 30*51.
• Verbose.net - Dedicated to the natural order of the universe and to the irrational and logical chaos it presents.
• Wikipedia - Mathematical constant - A list of constants with links to more detailed information.
• World of Numbers - Includes a collection of randomly gathered numbers, curios, puzzles, palindromes and primes.