A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2419956 can be evenly divided by 1 2 3 4 6 7 9 11 12 14 18 21 22 27 28 33 36 42 44 54 63 66 77 81 84 97 99 108 126 132 154 162 189 194 198 231 252 291 297 308 324 378 388 396 462 567 582 594 679 693 756 873 891 924 1,067 1,134 1,164 1,188 1,358 1,386 1,746 1,782 2,037 2,079 2,134 2,268 2,619 2,716 2,772 3,201 3,492 3,564 4,074 4,158 4,268 5,238 6,111 6,237 6,402 7,469 7,857 8,148 8,316 9,603 10,476 12,222 12,474 12,804 14,938 15,714 18,333 19,206 22,407 24,444 24,948 28,809 29,876 31,428 36,666 38,412 44,814 54,999 57,618 67,221 73,332 86,427 89,628 109,998 115,236 134,442 172,854 201,663 219,996 268,884 345,708 403,326 604,989 806,652 1,209,978 and 2,419,956, with no remainder.
Since 2,419,956 cannot be divided by just 1 and 2,419,956, it is not a prime number.