A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3872050 can be evenly divided by 1 2 5 7 10 13 14 23 25 26 35 37 46 50 65 70 74 91 115 130 161 175 182 185 230 259 299 322 325 350 370 455 481 518 575 598 650 805 851 910 925 962 1,150 1,295 1,495 1,610 1,702 1,850 2,093 2,275 2,405 2,590 2,990 3,367 4,025 4,186 4,255 4,550 4,810 5,957 6,475 6,734 7,475 8,050 8,510 10,465 11,063 11,914 12,025 12,950 14,950 16,835 20,930 21,275 22,126 24,050 29,785 33,670 42,550 52,325 55,315 59,570 77,441 84,175 104,650 110,630 148,925 154,882 168,350 276,575 297,850 387,205 553,150 774,410 1,936,025 and 3,872,050, with no remainder.
Since 3,872,050 cannot be divided by just 1 and 3,872,050, it is not a prime number.