Productive number

Number $M$ has the following characteristics:

1. All the digits of $M$ are different.
2. The product of any two adjacent digits in $M$ is also a number included in $M$ .

For example: 241836 satisfies the two conditions because the products of $2\times 4=8$ , $4\times 1=4$ , $1\times 8=8$ , $8\times 3=24$ , and $3 \times 6=18$ are found in $M$ .

Find the largest of such number $M$ .