Proof Converse of Fermat's Theorem Is False by producing a counterexample; Euler Totient function

Homework problem 16, Section 6 Underwood Dudley Textbook(reviewed by the "highly acclaimed" internet Sorcerer). The author provided a "broad hint" which was actually quite narrow which was to consider the integer 340 (mod 341). The student is to show 341 is NOT prime, but 340 congruent to 1 mod 341 providing a counterexample and proving converse of FLT is not true. nherinadarr ​⁠ lucidly taught confused math students illuminating instances of this concept. (She speaks Tagalog) Nagwa Classes App claimed to have "Homer Simpson" proof. Maine resident Whit Ford, software developer March 2018, exposition of product notation video of Euler phi function an excellent tutorial. Freeport math teacher Austin Dryer makes a difference.
Third grade teacher Sophia DeLoretto-Chudy has a right to express her view on social media, but we learned that independent school districts sometimes have written prohibitions regarding an educator posting specific detail about employee evaluations/corrective measures to improve teacher classroom effectiveness, civility towards colleagues, respect for administrators, prompt response to emails from concerned parents and other behavior quirks that could diminish effective/healthy interactions with students. Read the germane commentary by PreSchool Autism Teacher Janna Bedoyan