N is Nseries. The N series focuses on entertainment audio and video.
The c after the number usually means CLASSIC in English, which means classic, first-class and excellent. Some c means it is the mainland Chinese version.
Others are E. That is Eseries. The E series is an all-round business series
Although the Eseries focuses more on business functions, it is no worse than the Nseries in terms of entertainment. Moreover, the E series has higher performance.
You can simply compare products with the same price range. E.N series mobile phones
NOKIA’s most high-end product is not the N95, but the E90