Q: Is 671,840 a Prime Number?
A: No, 671,840 is not a prime number.
A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 671840 can be evenly divided by 1 2 4 5 8 10 13 16 17 19 20 26 32 34 38 40 52 65 68 76 80 85 95 104 130 136 152 160 170 190 208 221 247 260 272 304 323 340 380 416 442 494 520 544 608 646 680 760 884 988 1,040 1,105 1,235 1,292 1,360 1,520 1,615 1,768 1,976 2,080 2,210 2,470 2,584 2,720 3,040 3,230 3,536 3,952 4,199 4,420 4,940 5,168 6,460 7,072 7,904 8,398 8,840 9,880 10,336 12,920 16,796 17,680 19,760 20,995 25,840 33,592 35,360 39,520 41,990 51,680 67,184 83,980 134,368 167,960 335,920 and 671,840, with no remainder.
Since 671,840 cannot be divided by just 1 and 671,840, it is not a prime number.