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C Preprocessor Problems (MDK Lite with STM32F1)

I was trying to create an equation that told me how many flash blocks (pages) it would take to store some data I need. This may take up exactly a certain number of Flash blocks (pages), but more likely there will be spillover and part of (well, all of) another flash block will be needed.  The C preprocessor gives wrong calculations for 2 of the three methods I have tried. All 3 methods work on Compiler Explorer and the freebie IDE that comes from the chip manufacturer.  Maybe there is something I am doing wrong, but so far it escapes me. Is this possibly a compiler bug?

// From stm32f1xx_hal_flash_ex.h:
// #define FLASH_PAGE_SIZE          0x400U

// From my code: **Choose only one of the NUM_ITEMS**
#define  ITEM_SIZE  224UL
#define  NUM_ITEMS  64 // 64*224=14336 : 14 flash blocks
#define  NUM_ITEMS  66 // 66*224=14784 : 14.44 --> 15 flash blocks


// ORIGINAL MACRO: DOES NOT WORK. ALWAYS GIVES 14
#define  BLOCKS_FULL  ((NUM_ITEMS*ITEM_SIZE)/FLASH_PAGE_SIZE)
#define  REMAINDER    ((NUM_ITEMS*ITEM_SIZE)%FLASH_PAGE_SIZE)
#if REMAINDER == 0
  #define  NUM_BLOCKS1  BLOCKS_FULL
#else
  #define  NUM_BLOCKS1  (BLOCKS_FULL+1)  // Partial extra block
#endif


// ALTERNATE MACRO 1:  OK (14 or 15)
#define  NUM_BLOCKS2 (((NUM_ITEMS*ITEM_SIZE) + (FLASH_PAGE_SIZE-1)) / FLASH_PAGE_SIZE)


// ALTERNATE MACRO 2:  NOPE, SAME ISSUE AS ORIG? ALWAYS GIVES 14
#define  FLASH_TOTAL   (NUM_ITEMS*ITEM_SIZE)
#define  FLASH_BLOCKS  (FLASH_TOTAL/FLASH_PAGE_SIZE)
#if FLASH_TOTAL == (FLASH_BLOCKS * FLASH_PAGE_SIZE)
  #define  NUM_BLOCKS3  FLASH_BLOCKS
#else
  #define  NUM_BLOCKS3  (FLASH_BLOCKS+1)
#endif