Factoris (Popularity: )

Online calculator that factorizes large numbers, specified by formula.

Factorization Using the Elliptic Curve Method (Popularity: )

Java applet that can be used to find 20- or 30-digit factors of numbers or ...

Explaining the Divisibility Rules (Popularity: )

Proof of the elementary division rules, plus some lesser-known rules for larger divisors and other ...

FactorWorld (Popularity: )

Dedicated to algorithms and computational results on integer factorization. Includes links to papers, downloadable software, ...

The Anti-Divisor (Popularity: )

A definition and description of the Anti-Divisor, and some related results.

Divisibility War (Popularity: )

A card game to teach divisibility rules.

Sierpinski Problem (Popularity: )

Sierpinski proved there exist infinitely many odd integers k such that k*2^n+1 is composite for ...

The XYYXF Project (Popularity: )

A collaborative project to produce the factorizations of x^y + y^x for 1<y<x<101.

I Love Binary, Primes, and Factors (Popularity: )

Divisibility, primes and binary numbers.

The Factor Zone (Popularity: )

Aimed at grade school students and teachers, includes course guidelines, worksheets, and factor tables up ...

N!+-1 Factoring Status (Popularity: )

Factoring efforts that have been made so far on numbers of the form n!+-1 using ...

Robinson Primes (Popularity: )

An analysis of problems relating to the numbers k.2^n+-1, primes, and factor patterns, including the ...

Fermat Search (Popularity: )

Leonid Durman's Fermat number factoring site and program.

Aliquot Sequences (Popularity: )

Statistics by Wolfgang Creyaufmueller, including many tables and links to factoring sites and software.

Factors of Numbers near Googolplex (Popularity: )

This table includes all known prime factors of the numbers in the range 10^(10^100) to ...

Divisibility Tests (Popularity: )

Jim Loy explains the divisibility rules up to 11, including a detailed study of 7.

Factorization of RSA-155 (Popularity: )

Announcement of factorization of a 512-bit RSA key using the General Number Field Sieve (GNFS).

Multiply Perfect Numbers (Popularity: )

Up-to-date information on multiperfect numbers and searchable database maintained by Achim Flammenkamp.

Brilliant Numbers (Popularity: )

Tables of maximal and minimal numbers with two, three or four prime factors of the ...

On a Generalization of Perfect Numbers (Popularity: )

J. L. Pe introduces perfect numbers relative to an arithmetical function f. Under this scheme, ...