As far as I can tell, all 5 digit numbers are potential zip codes, so there are 99999 + 1 potential zip codes, or 100,000. Many of these are not actually is use.
Well, honey, the largest 12-digit number with repeated digits allowed is 9,999,999,999,999. I mean, unless you want to get fancy and start throwing in letters or emojis, but I doubt that's what you're looking for. So there you have it, the biggest 12-digit number you can get with the same digit repeated over and over again.
9x8x7x6x5x4x3x2x1 or 9! which equals 362880 possible combinations if no digits are repeated
If you include 0000, ten thousand unique four digit codes are possible.
10*9*8*7*6=30,240
The number of 4 digit codes, using different digits, is 10*9*8*7 = 5040. However, computer passwords can, usually, have repeated digits and, if that is allowed, you can have 104 = 10000 codes.
Well, honey, the largest 12-digit number with repeated digits allowed is 9,999,999,999,999. I mean, unless you want to get fancy and start throwing in letters or emojis, but I doubt that's what you're looking for. So there you have it, the biggest 12-digit number you can get with the same digit repeated over and over again.
9x8x7x6x5x4x3x2x1 or 9! which equals 362880 possible combinations if no digits are repeated
There are 4 possible numbers if the digits are not repeated; 18 if they are. Those are 3-digit numbers, assuming that zero would not be a leading digit. If zero is allowed for a leading digit, then you can have 6 for the non repeated, and 27 if repetition.
999,999,999,999
100,000,000,000
If you include 0000, ten thousand unique four digit codes are possible.
10*9*8*7*6=30,240
This permutation problem depends on whether the numbers are allowed to be repeated. If they are, there are a possible 9999 numbers, starting with 0001 and running sequentially to 9999. If they are not allowed to be repeated, there are a possible 5040 combinations.
The number of 4 digit codes, using different digits, is 10*9*8*7 = 5040. However, computer passwords can, usually, have repeated digits and, if that is allowed, you can have 104 = 10000 codes.
The first digit would have to be 1, the remaining digits, zero.
36n where n is the number of digits allowed in the plate. If a blank space is acceptable as a digit, then that becomes 37n.
9876