A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 790944 can be evenly divided by 1 2 3 4 6 7 8 11 12 14 16 21 22 24 28 32 33 42 44 48 56 66 77 84 88 96 107 112 132 154 168 176 214 224 231 264 308 321 336 352 428 462 528 616 642 672 749 856 924 1,056 1,177 1,232 1,284 1,498 1,712 1,848 2,247 2,354 2,464 2,568 2,996 3,424 3,531 3,696 4,494 4,708 5,136 5,992 7,062 7,392 8,239 8,988 9,416 10,272 11,984 14,124 16,478 17,976 18,832 23,968 24,717 28,248 32,956 35,952 37,664 49,434 56,496 65,912 71,904 98,868 112,992 131,824 197,736 263,648 395,472 and 790,944, with no remainder.
Since 790,944 cannot be divided by just 1 and 790,944, it is not a prime number.