12321, 54345, 10101, 42124, 81718 etc....
999, 1001.
There are 90 palindromic numbers between 100 and 1000
11000
1100
As 20569.8 is not palindromic, any number that is like it must contain that property and similarly be non-palindromic, so no.
999, 1001.
There are not just 13 non-palindromic numbers. Most numbers are non-palindromic.
There are 90 palindromic numbers between 100 and 1000
11000
1100
No.
Nobody went out to create them: some numbers simply happen to be palindromic and others don't.
{141, 444}, {232, 353} are two possible sets.
infinite
777717711771817718817...
No.
there are 10 palindromic numbers between 9000 and 10000 9009,9119,9229,9339,9449,9559,9669,9779,9889,9999!!!