A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3671460 can be evenly divided by 1 2 3 4 5 6 9 10 12 13 15 18 20 26 27 30 36 39 45 52 54 60 65 78 90 108 117 130 135 156 180 195 234 260 270 351 390 468 523 540 585 702 780 1,046 1,170 1,404 1,569 1,755 2,092 2,340 2,615 3,138 3,510 4,707 5,230 6,276 6,799 7,020 7,845 9,414 10,460 13,598 14,121 15,690 18,828 20,397 23,535 27,196 28,242 31,380 33,995 40,794 47,070 56,484 61,191 67,990 70,605 81,588 94,140 101,985 122,382 135,980 141,210 183,573 203,970 244,764 282,420 305,955 367,146 407,940 611,910 734,292 917,865 1,223,820 1,835,730 and 3,671,460, with no remainder.
Since 3,671,460 cannot be divided by just 1 and 3,671,460, it is not a prime number.