A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 2838752 can be evenly divided by 1 2 4 7 8 14 16 19 23 28 29 32 38 46 56 58 76 92 112 116 133 152 161 184 203 224 232 266 304 322 368 406 437 464 532 551 608 644 667 736 812 874 928 1,064 1,102 1,288 1,334 1,624 1,748 2,128 2,204 2,576 2,668 3,059 3,248 3,496 3,857 4,256 4,408 4,669 5,152 5,336 6,118 6,496 6,992 7,714 8,816 9,338 10,672 12,236 12,673 13,984 15,428 17,632 18,676 21,344 24,472 25,346 30,856 37,352 48,944 50,692 61,712 74,704 88,711 97,888 101,384 123,424 149,408 177,422 202,768 354,844 405,536 709,688 1,419,376 and 2,838,752, with no remainder.
Since 2,838,752 cannot be divided by just 1 and 2,838,752, it is not a prime number.