Science: Prime

A prime number is one which is divisible only by itself and 1. Thus 7, 13, 17, and 23 are prime numbers. In Chicago, one Samuel I. Krieger covered 72 sheets of foolscap paper, wore six pencils to stubs. Last week he announced a 72-digit prime number, challenged the world to show him a bigger one. His number: 231,584,178,474,632,390,847,141,970,017,375,815,706,539,969,331,281,128,078,915,826,259,279,871.

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