Specific Numbers

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.
http://arxiv.org/abs/math.NT/0006089/

Arabic numerals
Describes the history of the Arabic numeral system that is in use nearly all over the world today.
http://www-history.mcs.st-andrews.ac.uk/history/HistTopics/Arabic_numerals.html

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.
http://mathforum.org/library/drmath/view/57575.html

Catalan Number -- MathWorld
Illustration of the Catalan numbers related to Euler's polygon division problem.
http://mathworld.wolfram.com/CatalanNumber.html

FAQ on Special Numbers
Answers to Frequently asked questions about special numbers.
http://www.faqs.org/faqs/sci-math-faq/specialnumbers/

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.
http://www.mcs.surrey.ac.uk/Personal/R.Knott/Fibonacci/fibnat.html

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.
http://www.meden.demon.co.uk/Mathematics/S-Numbers/S-Numbers.html

Fun With Numbers
Includes some lists of numerals, relating to basic operations performed on certain constants. Not updated since 1995.
http://www.newdream.net/~sage/old/numbers/

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.
http://mathpages.com/home/kmath153.htm

Golden Ratio and Fibonacci Numbers
Provides information about the golden ratio and Fibonacci numbers, and how they relate to biology, art, and ancient Egyptian art.
http://www.geocities.com/CapeCanaveral/Station/8228/

37 Heaven
Collects information around the number thirty-seven.
http://magliery.com/37/

Indian numerals
Describes the history of the indian numeral system.
http://www-history.mcs.st-andrews.ac.uk/history/HistTopics/Indian_numerals.html

Inverse Symbolic Calculator
A set of programs and specialized tables of mathematical constants dedicated to the identification of real numbers.
http://oldweb.cecm.sfu.ca/projects/ISC/ISCmain.html

Jewish Encyclopedia: Numbers and Numerals
Discusses the uses and symbolism of various numbers in Hebrew literature.
http://www.jewishencyclopedia.com/view.jsp?artid=366&letter=N

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.
http://www.eingedi.org/666-2.html

Mathematical Constants and Computation
Essays, references, links, software.
http://numbers.computation.free.fr/Constants/constants.html

Number Gossip
Numerous special categories of numbers, searchable.
http://www.tanyakhovanova.com/Numbers/

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.
http://antwrp.gsfc.nasa.gov/htmltest/rjn_dig.html

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.
http://www.rossi.com/sqr2.htm

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.
http://stewy6.tripod.com/infinitesimal.htm

Sum Beastliness
Some simple mathematics associated with 666, the Number of the Beast.
http://web.onetel.com/~amygdala/articles/scimaths/666.html

Triangular Numbers
Properties of triangular numbers including reversible, happy, harshad, highly composite, deficient, abundant ones.
http://www.shyamsundergupta.com/triangle.htm

Vampire Numbers
Numbers with a factorization containing the same digits, e.g. 1530 = 30*51.
http://hjem.get2net.dk/jka/math/vampires

Verbose.net
Dedicated to the natural order of the universe and to the irrational and logical chaos it presents.
http://www.verbose.net/

Wikipedia - Mathematical constant
A list of constants with links to more detailed information.
http://en.wikipedia.org/wiki/Mathematical_constant

World of Numbers
Includes a collection of randomly gathered numbers, curios, puzzles, palindromes and primes.
http://www.worldofnumbers.com/