A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2045160 can be evenly divided by 1 2 3 4 5 6 8 9 10 12 13 15 18 19 20 23 24 26 30 36 38 39 40 45 46 52 57 60 65 69 72 76 78 90 92 95 104 114 115 117 120 130 138 152 156 171 180 184 190 195 207 228 230 234 247 260 276 285 299 312 342 345 360 380 390 414 437 456 460 468 494 520 552 570 585 598 684 690 741 760 780 828 855 874 897 920 936 988 1,035 1,140 1,170 1,196 1,235 1,311 1,368 1,380 1,482 1,495 1,560 1,656 1,710 1,748 1,794 1,976 2,070 2,185 2,223 2,280 2,340 2,392 2,470 2,622 2,691 2,760 2,964 2,990 3,420 3,496 3,588 3,705 3,933 4,140 4,370 4,446 4,485 4,680 4,940 5,244 5,382 5,681 5,928 5,980 6,555 6,840 7,176 7,410 7,866 8,280 8,740 8,892 8,970 9,880 10,488 10,764 11,115 11,362 11,960 13,110 13,455 14,820 15,732 17,043 17,480 17,784 17,940 19,665 21,528 22,230 22,724 26,220 26,910 28,405 29,640 31,464 34,086 35,880 39,330 44,460 45,448 51,129 52,440 53,820 56,810 68,172 78,660 85,215 88,920 102,258 107,640 113,620 136,344 157,320 170,430 204,516 227,240 255,645 340,860 409,032 511,290 681,720 1,022,580 and 2,045,160, with no remainder.
Since 2,045,160 cannot be divided by just 1 and 2,045,160, it is not a prime number.