Prove that 7×11×13 +13 is a composite number.

Updated on May 31, 2025 | By Learnzy Admin

7× 11 × 13 + 13 can be wriiten as 13 (7× 11 + 1).

=> 13 x (77 + 1)

=> 13 x 78

=> 13 x 2 x 39

Clearly, this has more than 2 factors.

So, 7× 11 × 13 + 13 is a composite number.

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