A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 535392 can be evenly divided by 1 2 3 4 6 8 9 11 12 13 16 18 22 24 26 32 33 36 39 44 48 52 66 72 78 88 96 99 104 117 132 143 144 156 169 176 198 208 234 264 286 288 312 338 352 396 416 429 468 507 528 572 624 676 792 858 936 1,014 1,056 1,144 1,248 1,287 1,352 1,521 1,584 1,716 1,859 1,872 2,028 2,288 2,574 2,704 3,042 3,168 3,432 3,718 3,744 4,056 4,576 5,148 5,408 5,577 6,084 6,864 7,436 8,112 10,296 11,154 12,168 13,728 14,872 16,224 16,731 20,592 22,308 24,336 29,744 33,462 41,184 44,616 48,672 59,488 66,924 89,232 133,848 178,464 267,696 and 535,392, with no remainder.
Since 535,392 cannot be divided by just 1 and 535,392, it is not a prime number.