A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2468466 can be evenly divided by 1 2 3 6 7 9 11 13 14 18 21 22 26 33 39 42 63 66 77 78 91 99 117 126 137 143 154 182 198 231 234 273 274 286 411 429 462 546 693 819 822 858 959 1,001 1,233 1,287 1,386 1,507 1,638 1,781 1,918 2,002 2,466 2,574 2,877 3,003 3,014 3,562 4,521 5,343 5,754 6,006 8,631 9,009 9,042 10,549 10,686 12,467 13,563 16,029 17,262 18,018 19,591 21,098 24,934 27,126 31,647 32,058 37,401 39,182 58,773 63,294 74,802 94,941 112,203 117,546 137,137 176,319 189,882 224,406 274,274 352,638 411,411 822,822 1,234,233 and 2,468,466, with no remainder.
Since 2,468,466 cannot be divided by just 1 and 2,468,466, it is not a prime number.