A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 5041890 can be evenly divided by 1 2 3 5 6 7 9 10 14 15 18 21 30 35 42 45 53 63 70 90 105 106 126 151 159 210 265 302 315 318 371 453 477 530 630 742 755 795 906 954 1,057 1,113 1,359 1,510 1,590 1,855 2,114 2,226 2,265 2,385 2,718 3,171 3,339 3,710 4,530 4,770 5,285 5,565 6,342 6,678 6,795 8,003 9,513 10,570 11,130 13,590 15,855 16,006 16,695 19,026 24,009 31,710 33,390 40,015 47,565 48,018 56,021 72,027 80,030 95,130 112,042 120,045 144,054 168,063 240,090 280,105 336,126 360,135 504,189 560,210 720,270 840,315 1,008,378 1,680,630 2,520,945 and 5,041,890, with no remainder.
Since 5,041,890 cannot be divided by just 1 and 5,041,890, it is not a prime number.