Imagine a number made up of a vast string of ones: 1111111…111. Specifically, 136,279,841 ones in a row. If we stacked up that many sheets of paper, the resulting tower would stretch into the ...

For more than 2,000 years, mathematicians have searched for a single example of an odd perfect number—and found none. Computers have tested candidates beyond 10^2,200, while 51 even perfect numbers ...