Q: What is the sum of all of the two-digit primes that are greater than 12 but less than 99 and are still prime when their two digits are interchanged?

Write your answer...

Submit

Still have questions?

Continue Learning about Basic Math

There are four pair of mirror primes.

Three of them.

373

18713, 18719, 18731, 18743, 18749 18731 is the center of the 5 primes. Notice that the distance from it to each on the the left and right is the same. Now do you see what a symmetrical primes is?

There are an infinite number of primes greater than any number given.

Related questions

The answer is 418. You are copying a MathCounts problem.

There are four pair of mirror primes.

No, 11 is the only palindromic prime with an even number of digits.

The longest string of consecutive numbers that are primes is two digits long, consisting of 2 and 3 only. There are no other consecutive numbers that are primes because no even numbers greater than 2 are primes.

The largest three digit prime number whose digits are all primes is 773.

The largest 3 digit number whose digits are all primes is 777. The largest 3 digit number with different prime digits is 753.

Three of them.

373

How about: 773

Composite

18713, 18719, 18731, 18743, 18749 18731 is the center of the 5 primes. Notice that the distance from it to each on the the left and right is the same. Now do you see what a symmetrical primes is?

A boatloadThere are in infinite number or primes, and they are still being discovered. The people who discover the prime that has more than 10 million digits will win $100,000. I'm pretty sure they're getting close, something like 9.8 million digits.