A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3224220 can be evenly divided by 1 2 3 4 5 6 10 12 15 17 20 29 30 34 51 58 60 68 85 87 102 109 116 145 170 174 204 218 255 290 327 340 348 435 436 493 510 545 580 654 870 986 1,020 1,090 1,308 1,479 1,635 1,740 1,853 1,972 2,180 2,465 2,958 3,161 3,270 3,706 4,930 5,559 5,916 6,322 6,540 7,395 7,412 9,265 9,483 9,860 11,118 12,644 14,790 15,805 18,530 18,966 22,236 27,795 29,580 31,610 37,060 37,932 47,415 53,737 55,590 63,220 94,830 107,474 111,180 161,211 189,660 214,948 268,685 322,422 537,370 644,844 806,055 1,074,740 1,612,110 and 3,224,220, with no remainder.
Since 3,224,220 cannot be divided by just 1 and 3,224,220, it is not a prime number.