Puzzle 27- factors

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 A teacher wrote down a number on the board asked the students to check the divisors of the number one by one. 

     The first student said that the number is divisible by 2.

      The second student said that the number is divisible by 3.

      And so on.

        The 30th student said that the number is divisible by 30.

       The last student said that the number is divisible by 31.

Now the teacher said that exactly two students who told about consecutive divisors are wrong. Which are those two numbers? 

The solution can be found here. 

 

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