Mysterious number 6174

March 2006

Number guessing puzzles

The first beautiful puzzle was by Yukio Yamamoto in Japan:

If you multiply two five digit numbers you can get the answer 123456789. Can you guess the two five digit numbers?

If you multiply two five digit numbers you can get the answer 123456789. Can you guess the two five digit numbers?

And the second, very similar puzzle:

If you multiply two five digit numbers you can get the answer 123456784. Can you guess the two five digit numbers?

HINT

Decompose the numbers into their prime factors to help you solve the puzzles.

123456789 = 3 x 3 x 3607 x 3803

and

123456784 = 24 x 112 x 43 x 1483

See the answers | Return to the article