4. Fermat's Little Theorem states that if p is a prime number and a is any positive integer less than p, then is congruent to 1 modulo p.To show that 117 is not a prime number, we can try to find a number a less than 117 that violates Fermat's Little Theorem.Let's try a = 2. Then, we have:Using modular exponentiation, we can calculate: