I was listening to the radio, and some self-proclaimed geek said that her phone number was "seven prime numbers."
At first, I interpreted this as "seven prime digits," which is probably what she meant.
But then it got me thinking, 23 has three prime numbers in it (2, 3, and 23), and 373 contains six primes!
The most primes you can pack into a seven-digit number is 22, so what number contains 22 primes?
Remember: neither 0 nor 1 are prime; and 5003 contains 5...
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