102 is the smallest three digit number with different digits.
The only number that ONLY has two and five as factors is 10, which has two digits, so there are no numbers that are three digits long and ONLY have two and five for factors. However, if you are asking what the largest three digit number that has two and five for factors, it would be the largest three digit number with ten as a factor, as ten the the LCM of two and five, and that would be 390.
smallest 8 digit number with three different digits
The factors of 36 are 1, 2, 3, 4, 6, 9, 12, 18, 36. None of them are three digits.
The largest three digit prime number whose digits are all primes is 773.
The largest number with no repeated digits is 9,876,543,210 although it is 10 digits long, the largest 3 digit number with no repeated digits is 987
All five digit numbers have three digits. The smallest five digit whole number is 10,000
We call them by the number of their digits. Two-digit number, three-digit number and so on.
The largest number with three digits is 999.