A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 898170 can be evenly divided by 1 2 3 5 6 7 10 13 14 15 21 26 30 35 39 42 47 49 65 70 78 91 94 98 105 130 141 147 182 195 210 235 245 273 282 294 329 390 455 470 490 546 611 637 658 705 735 910 987 1,222 1,274 1,365 1,410 1,470 1,645 1,833 1,911 1,974 2,303 2,730 3,055 3,185 3,290 3,666 3,822 4,277 4,606 4,935 6,110 6,370 6,909 8,554 9,165 9,555 9,870 11,515 12,831 13,818 18,330 19,110 21,385 23,030 25,662 29,939 34,545 42,770 59,878 64,155 69,090 89,817 128,310 149,695 179,634 299,390 449,085 and 898,170, with no remainder.
Since 898,170 cannot be divided by just 1 and 898,170, it is not a prime number.