A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 6193992 can be evenly divided by 1 2 3 4 6 7 8 12 14 21 23 24 28 42 46 49 56 69 84 92 98 138 147 161 168 184 196 229 276 294 322 392 458 483 552 588 644 687 916 966 1,127 1,176 1,288 1,374 1,603 1,832 1,932 2,254 2,748 3,206 3,381 3,864 4,508 4,809 5,267 5,496 6,412 6,762 9,016 9,618 10,534 11,221 12,824 13,524 15,801 19,236 21,068 22,442 27,048 31,602 33,663 36,869 38,472 42,136 44,884 63,204 67,326 73,738 89,768 110,607 126,408 134,652 147,476 221,214 258,083 269,304 294,952 442,428 516,166 774,249 884,856 1,032,332 1,548,498 2,064,664 3,096,996 and 6,193,992, with no remainder.
Since 6,193,992 cannot be divided by just 1 and 6,193,992, it is not a prime number.