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#20 Factor-finding mission
Set by Mary Ellis
154 has three prime factors (2, 7 and 11), but it can be divided by other numbers, including 1, 14, 22, 77 and 154. These are factors of 154, but not prime factors.
What is the smallest number that has four distinct prime factors? How many factors does this number have?
What is the next number after this that has the same total number of factors? (Hint: it isn’t a number with four distinct prime factors!)
What is the smallest number that has that same total number of factors?
Solution next week
