xxxx xxxx xxxx xxxx
The number 1-6 is the BIN number of the issuing bank.
Serial number of card 7- 12
The 0 bit of 13 represents the main card, and 1-9 represents the auxiliary card.
Bit 14 indicates the date when the statement was issued.
The number 15 represents the card number, and 1 will be added after the card is replenished.
16 check code