Quick,

Don't bother reaching for your calculator. To turn this 100-digit monster into its indivisible primes -- as in reducing 15 to the product of 3 and 5 -- would ordinarily require the undivided attention of a supercomputer for as long as two months. But last week the record-size problem was solved after just 26 days by a group of more than 50 smaller machines scattered across the U.S., Europe and Australia.

Employing a technique called distributed processing, Arjen Lenstra, a Dutch-born computer scientist working as a visiting professor at the University of Chicago, broke the task into smaller pieces and dispatched them over ordinary phone lines to computers at universities and corporations. The results were then compiled by minicomputers at a Digital Equipment lab in Palo Alto, Calif. The success of the ad hoc network, one of the largest ever assembled, raises problems for cryptographers and intelligence agencies, whose code solutions are often based on the prime factors of long, hard-to-solve integers. But it certainly demonstrates the enormous power of small computers linked together by electronic mail. Their answer: 86,759,222,313,428,390,812, 218,077,095,850,708,048,977 X 108,488,104,853,637,470, 612,961,399,842,972,948,409,834,611,525,790,577,216, 753.