 2097152 is 0x200000, and storing this value needs more than two bytes.Therefore, FAT32 introduced a new 32-bit value in the FAT32 boot sector immediately following the 32-bit value for the total number of sectors introduced in the FAT16B variant.The boot record extensions introduced with DOS 4.0 start with a magic 40 (0x28) or 41 (0x29).