$799777779779979$ and $111111811818111$ are numbers of $2$ non-zero digits that can be factored into $2$-digit numbers. They are $97$-smooth numbers.
Are there any larger examples?
Large 2-digit numbers that factor into 2-digit numbers.
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combinatorics
number-theory
recreational-mathematics
prime-factorization
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1"numbers of 2 non-zero digits" means what? – 2017-02-03
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1Note that "friable" is a more descriptive and more modern term than the conventional "smooth" in this context. – 2017-02-03
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1According to my calculation, a larger example must have more than $20$ digits. The ratio of smooth numbers decreases drastically , so it is well possible that no larger example exists. – 2017-02-04