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Very hard number puzzle

iamaelephant

Diamond Member
Jul 25, 2004
3,816
1
81
I have in mind five five-digit numbers. For each of them, five of the following ten statements are true;

1. It contains two zeros
2. It is a perfect cube
3. It is the product of five successive numbers
4. It is a perfect square
5. The central digit is a 5
6. The sum of the digits is a square or cube, or has both its digits the same
7. It is not prime, but has only one prime factor
8. It is a power greater than the third
9. It is a palindromic square of a palindrome
10. The first and last digits put together in that order form a perfect square

What are the five numbers?
 

Moonbeam

Elite Member
Nov 24, 1999
74,747
6,762
126
The first and last digits put together in that order form a perfect square
Probably false or deceptive as it's not too clear to me what this means.

The first and last digits of 12345 are 1,5 or 1,2;4,5 depending because digits are 2 or more. Strictly speaking could this not also read, The first and last digit put together in that order form a perfect square if just one digit from each end were sought?
 

iamaelephant

Diamond Member
Jul 25, 2004
3,816
1
81
First and last means first and last, not first two and last two. It's pretty clear in my opinion.
 

Moonbeam

Elite Member
Nov 24, 1999
74,747
6,762
126
Originally posted by: iamaelephant
First and last means first and last, not first two and last two. It's pretty clear in my opinion.

Really? It would be the first and last digit, then, not first and last digits.

What are the first and last digits here? 22ttttt77. How about the first and last digit.