A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3827208 can be evenly divided by 1 2 3 4 6 7 8 11 12 14 19 21 22 24 28 33 38 42 44 56 57 66 76 77 84 88 109 114 132 133 152 154 168 209 218 228 231 264 266 308 327 399 418 436 456 462 532 616 627 654 763 798 836 872 924 1,064 1,199 1,254 1,308 1,463 1,526 1,596 1,672 1,848 2,071 2,289 2,398 2,508 2,616 2,926 3,052 3,192 3,597 4,142 4,389 4,578 4,796 5,016 5,852 6,104 6,213 7,194 8,284 8,393 8,778 9,156 9,592 11,704 12,426 14,388 14,497 16,568 16,786 17,556 18,312 22,781 24,852 25,179 28,776 28,994 33,572 35,112 43,491 45,562 49,704 50,358 57,988 67,144 68,343 86,982 91,124 100,716 115,976 136,686 159,467 173,964 182,248 201,432 273,372 318,934 347,928 478,401 546,744 637,868 956,802 1,275,736 1,913,604 and 3,827,208, with no remainder.
Since 3,827,208 cannot be divided by just 1 and 3,827,208, it is not a prime number.