A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 1176252 can be evenly divided by 1 2 3 4 6 7 11 12 14 19 21 22 28 33 38 42 44 57 66 67 76 77 84 114 132 133 134 154 201 209 228 231 266 268 308 399 402 418 462 469 532 627 737 798 804 836 924 938 1,254 1,273 1,407 1,463 1,474 1,596 1,876 2,211 2,508 2,546 2,814 2,926 2,948 3,819 4,389 4,422 5,092 5,159 5,628 5,852 7,638 8,778 8,844 8,911 10,318 14,003 15,276 15,477 17,556 17,822 20,636 26,733 28,006 30,954 35,644 42,009 53,466 56,012 61,908 84,018 98,021 106,932 168,036 196,042 294,063 392,084 588,126 and 1,176,252, with no remainder.
Since 1,176,252 cannot be divided by just 1 and 1,176,252, it is not a prime number.