What can you say about numbers that have exactly 3 factors?
Give some examples of numbers with 4 factors. What do they have in common?
Give some examples of numbers with 5 factors. What do they have in common?
What about numbers with 6 factors?
How many factors does 72 have?
Can you find a connection between the number of factors of 72 and the exponents in the expression giving the factorisation of 72 into primes?72=2^3\times3^2
Give examples of some numbers with 12 factors. What is the smallest number with 12 factors.?
What is the smallest number with exactly fourteen divisors?
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