8 digit palindrome = 9*10*10*10 = 9000
but how to get 8 digit prime palindromes ?
In the above question, we have to find number of 8 digit prime palindromes but your answer includes both prime and non-prime palindromes.
For ex- 20000002
Is it a prime palindrome. ??
Let the digits of our 8-digit palindrome n be d1d2d3d4d4d3d2d1. Then the palindrome has the form
Such n cannot be prime because gcd(10000001,1000010,100100,11000)=11.
So there are NO 8-digit prime palindromes. (However, there are prime palindromes with an odd number of digits, e.g. 101101, 1030110301, 9868998689, 98010899801089.)
Even no of digits cannot be prime number so no pallindromes
check this link https://math.stackexchange.com/questions/2255780/how-many-8-digit-palindromes-are-prime/2255829#2255829?newreg=b6c8ce28f3fc4ae68100499c4852f5a5
X->YZ , Y->XZ , ...