A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 3230000 can be evenly divided by 1 2 4 5 8 10 16 17 19 20 25 34 38 40 50 68 76 80 85 95 100 125 136 152 170 190 200 250 272 304 323 340 380 400 425 475 500 625 646 680 760 850 950 1,000 1,250 1,292 1,360 1,520 1,615 1,700 1,900 2,000 2,125 2,375 2,500 2,584 3,230 3,400 3,800 4,250 4,750 5,000 5,168 6,460 6,800 7,600 8,075 8,500 9,500 10,000 10,625 11,875 12,920 16,150 17,000 19,000 21,250 23,750 25,840 32,300 34,000 38,000 40,375 42,500 47,500 64,600 80,750 85,000 95,000 129,200 161,500 170,000 190,000 201,875 323,000 403,750 646,000 807,500 1,615,000 and 3,230,000, with no remainder.
Since 3,230,000 cannot be divided by just 1 and 3,230,000, it is not a prime number.