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Hello there.

This is Numberphile. We mainly post videos about mathematics and just numbers in general.

6174

6174 is also known as Kaprekar's Constant.

This video features University of Nottingham physics professor Roger Bowley, who is also featured on our Sixty Symbols channel at http://www.youtube.com/sixtysymbols

69!

69!

8128 and Perfect Numbers

8128 and Perfect Numbers