Determine the smallest base ten positive palindrome with exactly 4 distinct prime factors.
(In reply to re: No Subject
That "shortcut" is not particularly reliable. All even-digit palindromes are divisible by 11, but only 1 out 11 odd digit palindromes is divisible by 11. It is just sheer chance that 858 is divisible by 11, so the shortcut appears to work.
From Charlie's list, for example, 24242 = 2 * 17 * 23 * 31 is the smallest 5 digit palindrome with exactly 4 distinct prime factors, but it would not be found by this "shortcut".