121 because 2x1x1=2 and 11x11=121
98
The largest 10-digit number with no digit repeated is 9876543210 !
product means multiplication. so a 2 digit number multiplied by a 4 digit number. 80 x 6250 = 500,000 80 can be your 2 digit number 6250 can be your 4 digit number
The number of six digit numbers that you can make from ten different digits ifrepetitions of same digit on the six digit number is allowed is 1 000 000 numbers(including number 000 000).If no repetitions of the the same digit are allowed then you have:10P6 = 10!/(10-6)! = 151 200 different six digit numbers(six digit permutations form 10 different digits).
Assuming that 2356 is a different number to 2365, then: 1st digit can be one of four digits (2356) For each of these 4 first digits, there are 3 of those digits, plus the zero, meaning 4 possible digits for the 2nd digit For each of those first two digits, there is a choice of 3 digits for the 3rd digit For each of those first 3 digits, there is a choice of 2 digits for the 4tj digit. Thus there are 4 x 4 x 3 x 2 = 96 different possible 4 digit numbers that do not stat with 0 FM the digits 02356.
81
1
121
225 = (15)2 2*2*5=20 3 digits in 225
It can have up to 5 digits.
81
Six.
49
Every square of a 4 digit number has more than four digits.
You had me until "product." The product of 4 digits can't be prime.
81...........
121 121 = 11^2 1 x 2 x 1 = 2