We know different number systems. But how many of us know about the constants associated about the different number systems. I will give some examples, example 1: if you divide the sum of any two digit number and its reverse by the sum of the two digits comprising the number, then the result is always 11 in decimal system. So irrespective of the 2-digit number you choose, the result will always be 11, So 11 is costant of operation of the above process. There are a lot of such constants for every number system. These constants are known as MEMI constants.