**From New Scientist #2774, 21st August 2010** [link]

I am a bit vague about my bank security number –

It is a four figure number (or possibly five);

It uses four different digits (or possibly five);

The first digit is four (or possibly five);

The second digit is four (or possibly five) and none of the other digits is smaller;

The number is a prime multiplied by four (or possibly five);

If you reverse the order of the digits you get a number which is the product of four (or possibly five) different primes;

In four (or possibly five) of these statements my first guess is correct.

What is my bank security number?

[enigma1609]

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The following Python program runs in 128ms.

Solution:The security number is 5468.