A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 8260650 can be evenly divided by 1 2 3 5 6 9 10 15 18 25 27 29 30 45 50 54 58 75 87 90 135 145 150 174 211 225 261 270 290 422 435 450 522 633 675 725 783 870 1,055 1,266 1,305 1,350 1,450 1,566 1,899 2,110 2,175 2,610 3,165 3,798 3,915 4,350 5,275 5,697 6,119 6,330 6,525 7,830 9,495 10,550 11,394 12,238 13,050 15,825 18,357 18,990 19,575 28,485 30,595 31,650 36,714 39,150 47,475 55,071 56,970 61,190 91,785 94,950 110,142 142,425 152,975 165,213 183,570 275,355 284,850 305,950 330,426 458,925 550,710 826,065 917,850 1,376,775 1,652,130 2,753,550 4,130,325 and 8,260,650, with no remainder.
Since 8,260,650 cannot be divided by just 1 and 8,260,650, it is not a prime number.