A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2569980 can be evenly divided by 1 2 3 4 5 6 7 10 12 14 15 20 21 28 29 30 35 42 58 60 70 84 87 105 116 140 145 174 203 210 211 290 348 406 420 422 435 580 609 633 812 844 870 1,015 1,055 1,218 1,266 1,477 1,740 2,030 2,110 2,436 2,532 2,954 3,045 3,165 4,060 4,220 4,431 5,908 6,090 6,119 6,330 7,385 8,862 12,180 12,238 12,660 14,770 17,724 18,357 22,155 24,476 29,540 30,595 36,714 42,833 44,310 61,190 73,428 85,666 88,620 91,785 122,380 128,499 171,332 183,570 214,165 256,998 367,140 428,330 513,996 642,495 856,660 1,284,990 and 2,569,980, with no remainder.
Since 2,569,980 cannot be divided by just 1 and 2,569,980, it is not a prime number.