The first two English letters are called crowns, and the last eight Arabic numerals are called numbers.
26 English letters MINUS V, and there are 25. A to J in groups of ten, KLMNO in groups of five, P to Z 10. These three groups are matched with each other or with themselves to form nine groups. The batch of RMB printing is the order of large groups. Specifically, the fourth set and the fifth set have different names for large groups. In the fourth set, AP group 1, PA group 2, PK group 3, AK group 4, KP group 5 and AA group 6. If each group is printed completely, it will be 100 or 50 crowns, but generally not all numbers will be sent. The fifth set of RMB means that 100 at the beginning of AA is the first group.
As for the numbers, each prefix starts with 0000000 1 and ends with 100000000 (note that there are eight zeros), totaling 100 million.