5
12,346
1023456789
10234567
5
none
5
0123456789
10234567
Since there are only five different digits, a 6-digit number can only be generated if a digit can be repeated. If digits can be repeated, the smallest 6-digit number is 111111.
100,000,000,000
102
103
The first digit would have to be 1, the remaining digits, zero.