Answer: Caesarion.
Some extra relevant information:
Julius Caesar, the famous Roman dictator and military general, is widely known by his full name, rather than a specific nickname. While there are no specific nicknames associated with Julius Caesar, his name itself has become an iconic symbol of power, leadership, and ambition. Caesar’s name is often used as a reference to great rulers and conquerors throughout history, emphasizing his lasting legacy as one of the most influential figures in the ancient world.