# A number theory problem by A Former Brilliant Member

How many 8-digit palindromic numbers are composite (i.e. not prime)?

Details and Assumptions:

• A palindromic number is a number that remains the same when its digits are reversed: for example, $77$ and $15851.$
• Assume that numbers are written without leading zeros. For instance, $00022000$ is not a valid 8-digit palindrome, but $10000001$ is.
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