A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3603180 can be evenly divided by 1 2 3 4 5 6 7 10 12 14 15 20 21 23 28 30 35 42 46 60 69 70 84 92 105 115 138 140 161 210 230 276 322 345 373 420 460 483 644 690 746 805 966 1,119 1,380 1,492 1,610 1,865 1,932 2,238 2,415 2,611 3,220 3,730 4,476 4,830 5,222 5,595 7,460 7,833 8,579 9,660 10,444 11,190 13,055 15,666 17,158 22,380 25,737 26,110 31,332 34,316 39,165 42,895 51,474 52,220 60,053 78,330 85,790 102,948 120,106 128,685 156,660 171,580 180,159 240,212 257,370 300,265 360,318 514,740 600,530 720,636 900,795 1,201,060 1,801,590 and 3,603,180, with no remainder.
Since 3,603,180 cannot be divided by just 1 and 3,603,180, it is not a prime number.