A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 6982976 can be evenly divided by 1 2 4 7 8 11 13 14 16 22 26 28 32 44 52 56 64 77 88 91 104 109 112 143 154 176 182 208 218 224 286 308 352 364 416 436 448 572 616 704 728 763 832 872 1,001 1,144 1,199 1,232 1,417 1,456 1,526 1,744 2,002 2,288 2,398 2,464 2,834 2,912 3,052 3,488 4,004 4,576 4,796 4,928 5,668 5,824 6,104 6,976 8,008 8,393 9,152 9,592 9,919 11,336 12,208 15,587 16,016 16,786 19,184 19,838 22,672 24,416 31,174 32,032 33,572 38,368 39,676 45,344 48,832 62,348 64,064 67,144 76,736 79,352 90,688 109,109 124,696 134,288 158,704 218,218 249,392 268,576 317,408 436,436 498,784 537,152 634,816 872,872 997,568 1,745,744 3,491,488 and 6,982,976, with no remainder.
Since 6,982,976 cannot be divided by just 1 and 6,982,976, it is not a prime number.