A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 946680 can be evenly divided by 1 2 3 4 5 6 7 8 10 12 14 15 20 21 23 24 28 30 35 40 42 46 49 56 60 69 70 84 92 98 105 115 120 138 140 147 161 168 184 196 210 230 245 276 280 294 322 343 345 392 420 460 483 490 552 588 644 686 690 735 805 840 920 966 980 1,029 1,127 1,176 1,288 1,372 1,380 1,470 1,610 1,715 1,932 1,960 2,058 2,254 2,415 2,744 2,760 2,940 3,220 3,381 3,430 3,864 4,116 4,508 4,830 5,145 5,635 5,880 6,440 6,762 6,860 7,889 8,232 9,016 9,660 10,290 11,270 13,524 13,720 15,778 16,905 19,320 20,580 22,540 23,667 27,048 31,556 33,810 39,445 41,160 45,080 47,334 63,112 67,620 78,890 94,668 118,335 135,240 157,780 189,336 236,670 315,560 473,340 and 946,680, with no remainder.
Since 946,680 cannot be divided by just 1 and 946,680, it is not a prime number.