A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 4860240 can be evenly divided by 1 2 3 4 5 6 7 8 10 11 12 14 15 16 20 21 22 24 28 30 33 35 40 42 44 48 55 56 60 66 70 77 80 84 88 105 110 112 120 132 140 154 165 168 176 210 220 231 240 263 264 280 308 330 336 385 420 440 462 526 528 560 616 660 770 789 840 880 924 1,052 1,155 1,232 1,315 1,320 1,540 1,578 1,680 1,841 1,848 2,104 2,310 2,630 2,640 2,893 3,080 3,156 3,682 3,696 3,945 4,208 4,620 5,260 5,523 5,786 6,160 6,312 7,364 7,890 8,679 9,205 9,240 10,520 11,046 11,572 12,624 14,465 14,728 15,780 17,358 18,410 18,480 20,251 21,040 22,092 23,144 27,615 28,930 29,456 31,560 34,716 36,820 40,502 43,395 44,184 46,288 55,230 57,860 60,753 63,120 69,432 73,640 81,004 86,790 88,368 101,255 110,460 115,720 121,506 138,864 147,280 162,008 173,580 202,510 220,920 231,440 243,012 303,765 324,016 347,160 405,020 441,840 486,024 607,530 694,320 810,040 972,048 1,215,060 1,620,080 2,430,120 and 4,860,240, with no remainder.
Since 4,860,240 cannot be divided by just 1 and 4,860,240, it is not a prime number.