The multiplication of the first 25 numbers can be calculated by multiplying them together. Here's the calculation:

1 × 2 × 3 × 4 × 5 × 6 × 7 × 8 × 9 × 10 × 11 × 12 × 13 × 14 × 15 × 16 × 17 × 18 × 19 × 20 × 21 × 22 × 23 × 24 × 25

The result of this multiplication is a very large number. It is approximately:

15,511,210,043,330,985,984,000,000

Please note that due to the size of the number, it is not practical to provide the exact value. The above approximation should give you an idea of the magnitude.