A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2705220 can be evenly divided by 1 2 3 4 5 6 7 9 10 12 14 15 18 19 20 21 28 30 35 36 38 42 45 57 60 63 70 76 84 90 95 105 113 114 126 133 140 171 180 190 210 226 228 252 266 285 315 339 342 380 399 420 452 532 565 570 630 665 678 684 791 798 855 1,017 1,130 1,140 1,197 1,260 1,330 1,356 1,582 1,596 1,695 1,710 1,995 2,034 2,147 2,260 2,373 2,394 2,660 3,164 3,390 3,420 3,955 3,990 4,068 4,294 4,746 4,788 5,085 5,985 6,441 6,780 7,119 7,910 7,980 8,588 9,492 10,170 10,735 11,865 11,970 12,882 14,238 15,029 15,820 19,323 20,340 21,470 23,730 23,940 25,764 28,476 30,058 32,205 35,595 38,646 42,940 45,087 47,460 60,116 64,410 71,190 75,145 77,292 90,174 96,615 128,820 135,261 142,380 150,290 180,348 193,230 225,435 270,522 300,580 386,460 450,870 541,044 676,305 901,740 1,352,610 and 2,705,220, with no remainder.
Since 2,705,220 cannot be divided by just 1 and 2,705,220, it is not a prime number.