A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 379080 can be evenly divided by 1 2 3 4 5 6 8 9 10 12 13 15 18 20 24 26 27 30 36 39 40 45 52 54 60 65 72 78 81 90 104 108 117 120 130 135 156 162 180 195 216 234 243 260 270 312 324 351 360 390 405 468 486 520 540 585 648 702 729 780 810 936 972 1,053 1,080 1,170 1,215 1,404 1,458 1,560 1,620 1,755 1,944 2,106 2,340 2,430 2,808 2,916 3,159 3,240 3,510 3,645 4,212 4,680 4,860 5,265 5,832 6,318 7,020 7,290 8,424 9,477 9,720 10,530 12,636 14,040 14,580 15,795 18,954 21,060 25,272 29,160 31,590 37,908 42,120 47,385 63,180 75,816 94,770 126,360 189,540 and 379,080, with no remainder.
Since 379,080 cannot be divided by just 1 and 379,080, it is not a prime number.