7000000001

This number is a prime.

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+ The largest emirp less than a googol of form 7*10^x+1, (case x=9). Note that the previous numbers of this form i.e., for x=1, 2, 4, 5, 8 are also emirps and for x=3, i.e., 7001 is only prime. [Loungrides]

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