154, 231, 308, 385, 462, 539, 616, 693, 770, 847, 924
There are many 4 digit numbers having 3 and 11 as factors. One of them is 1089 whose factors are 3,3,11,11.
1023, 1056 and just keep adding 33 until you get to 9999
You can select 12 numbers for the first digit, 11 numbers for the second digit, and 10 numbers for the third digit; so 12*11*10 = 1320 sets of 3 numbers can be made out of 12 different numbers.
420 and 840
All numbers have factors. Some factors have one digit. The factors of 24 are 1, 2, 3, 4, 6, 8, 12, 24 The single digit factors of 24 are 1, 2, 3, 4, 6 and 8.
333 3 11 111
Prime factors of 42 are: 2, 3 and 7
Using prime factorization, there are 2 three digit numbers with 9 factors: 512 and 768. There are no three digit numbers with 10 or more prime factors. 512=2^9 and 768=3*2^8
The squares of most 2 digit prime numbers. For example 2809, which is the square of 53, has 3 factors : 1, 53 and 2809 itself.
The prime factors of 81 are 3, 3, 3, and 3 - so the only two-digit factor is 27, which is 3 x 3 x 3.
3 digit numbers are lessthan 4 digit numbers
The common factors of 609 and 957 are 1, 3, 29 and 87. No 3-digit numbers.