A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 1465560 can be evenly divided by 1 2 3 4 5 6 8 9 10 12 15 18 20 23 24 27 30 36 40 45 46 54 59 60 69 72 90 92 108 115 118 120 135 138 177 180 184 207 216 230 236 270 276 295 345 354 360 414 460 472 531 540 552 590 621 690 708 828 885 920 1,035 1,062 1,080 1,180 1,242 1,357 1,380 1,416 1,593 1,656 1,770 2,070 2,124 2,360 2,484 2,655 2,714 2,760 3,105 3,186 3,540 4,071 4,140 4,248 4,968 5,310 5,428 6,210 6,372 6,785 7,080 7,965 8,142 8,280 10,620 10,856 12,213 12,420 12,744 13,570 15,930 16,284 20,355 21,240 24,426 24,840 27,140 31,860 32,568 36,639 40,710 48,852 54,280 61,065 63,720 73,278 81,420 97,704 122,130 146,556 162,840 183,195 244,260 293,112 366,390 488,520 732,780 and 1,465,560, with no remainder.
Since 1,465,560 cannot be divided by just 1 and 1,465,560, it is not a prime number.