A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2768976 can be evenly divided by 1 2 3 4 6 7 8 9 12 14 16 18 21 24 28 36 41 42 48 56 63 67 72 82 84 112 123 126 134 144 164 168 201 246 252 268 287 328 336 369 402 469 492 504 536 574 603 656 738 804 861 938 984 1,008 1,072 1,148 1,206 1,407 1,476 1,608 1,722 1,876 1,968 2,296 2,412 2,583 2,747 2,814 2,952 3,216 3,444 3,752 4,221 4,592 4,824 5,166 5,494 5,628 5,904 6,888 7,504 8,241 8,442 9,648 10,332 10,988 11,256 13,776 16,482 16,884 19,229 20,664 21,976 22,512 24,723 32,964 33,768 38,458 41,328 43,952 49,446 57,687 65,928 67,536 76,916 98,892 115,374 131,856 153,832 173,061 197,784 230,748 307,664 346,122 395,568 461,496 692,244 922,992 1,384,488 and 2,768,976, with no remainder.
Since 2,768,976 cannot be divided by just 1 and 2,768,976, it is not a prime number.