Five.
The five numbers are 11, 12, 15, 24, 36
If you mean, "What is the largest number of digits possible in the product of two 2-digit numbers" then 99 * 99 = 9801, or 4 digits. Anything down to 59 * 17 = 1003 will have 4 digits.
You had me until "product." The product of 4 digits can't be prime.
It can have 4 digits, because the highest possible two digit numbers 99*99=9801.
There are 15 of them.
from 3 digits (10x10) to 4 digits (99X99)
-21
There are three such numbers: 12, 24 and 36.
4 Give examples to support your answer please.
There are five such numbers: 11, 12, 15, 24 and 36.
If the question is about the product of all odd digits, the answer is 945. Otherwise the question does not make sense.
With 123 digits you can make 123 one-digit numbers.
2