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Counting Factors

Is there an efficient way to work out how many factors a large number has?

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Choose any 3 digits and make a 6 digit number by repeating the 3 digits in the same order (e.g. 594594). Explain why whatever digits you choose the number will always be divisible by 7, 11 and 13.

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Oh! Hidden Inside?

Find the number which has 8 divisors, such that the product of the divisors is 331776.

Just Repeat

Stage: 3 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

Just repeat!

Think of any three-digit number.
Repeat the digits


234 ....... 234 234

973 ...... 973 973

Both 6-digit numbers are divisible by 91.

Is this a coincidence?

Are there other patterns and connections?