A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 4123000 can be evenly divided by 1 2 4 5 7 8 10 14 19 20 25 28 31 35 38 40 50 56 62 70 76 95 100 124 125 133 140 152 155 175 190 200 217 248 250 266 280 310 350 380 434 475 500 532 589 620 665 700 760 775 868 875 950 1,000 1,064 1,085 1,178 1,240 1,330 1,400 1,550 1,736 1,750 1,900 2,170 2,356 2,375 2,660 2,945 3,100 3,325 3,500 3,800 3,875 4,123 4,340 4,712 4,750 5,320 5,425 5,890 6,200 6,650 7,000 7,750 8,246 8,680 9,500 10,850 11,780 13,300 14,725 15,500 16,492 16,625 19,000 20,615 21,700 23,560 26,600 27,125 29,450 31,000 32,984 33,250 41,230 43,400 54,250 58,900 66,500 73,625 82,460 103,075 108,500 117,800 133,000 147,250 164,920 206,150 217,000 294,500 412,300 515,375 589,000 824,600 1,030,750 2,061,500 and 4,123,000, with no remainder.
Since 4,123,000 cannot be divided by just 1 and 4,123,000, it is not a prime number.