A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2199288 can be evenly divided by 1 2 3 4 6 7 8 12 13 14 19 21 24 26 28 38 39 42 52 53 56 57 76 78 84 91 104 106 114 133 152 156 159 168 182 212 228 247 266 273 312 318 364 371 399 424 456 494 532 546 636 689 728 741 742 798 988 1,007 1,064 1,092 1,113 1,272 1,378 1,482 1,484 1,596 1,729 1,976 2,014 2,067 2,184 2,226 2,756 2,964 2,968 3,021 3,192 3,458 4,028 4,134 4,452 4,823 5,187 5,512 5,928 6,042 6,916 7,049 8,056 8,268 8,904 9,646 10,374 12,084 13,091 13,832 14,098 14,469 16,536 19,292 20,748 21,147 24,168 26,182 28,196 28,938 38,584 39,273 41,496 42,294 52,364 56,392 57,876 78,546 84,588 91,637 104,728 115,752 157,092 169,176 183,274 274,911 314,184 366,548 549,822 733,096 1,099,644 and 2,199,288, with no remainder.
Since 2,199,288 cannot be divided by just 1 and 2,199,288, it is not a prime number.