Prime Number with Prime Digits

  • Context: High School 
  • Thread starter Thread starter fibonacci235
  • Start date Start date
  • Tags Tags
    Prime
Click For Summary
SUMMARY

The discussion centers on the concept of prime numbers whose digits are all prime, with participants exploring whether such numbers have a specific name. The initial examples provided include single-digit primes (2, 3, 5, 7) and the two-digit prime 23. The conversation highlights that the property of being prime is independent of number representation, leading to the conclusion that no established name exists for these numbers. One participant proposes the term "Digital Primes" to describe this category.

PREREQUISITES
  • Understanding of prime numbers and their properties
  • Familiarity with number representation systems (e.g., base 10, binary, hexadecimal)
  • Knowledge of specific types of primes (e.g., Mersenne primes, palindromic numbers)
  • Basic concepts in number theory
NEXT STEPS
  • Research the properties of Mersenne primes and their significance in number theory
  • Explore the concept of palindromic numbers and their mathematical implications
  • Investigate the classification of prime numbers and their various types
  • Learn about base-dependent properties of numbers, including Happy numbers
USEFUL FOR

Mathematicians, number theorists, and anyone interested in the classification and properties of prime numbers.

fibonacci235
Messages
15
Reaction score
1
Is there a name for a prime number whose digits are all prime? The first several that I can think of are

2,3,5,7 and 23, 23 being the first double digit prime whose digits are all prime.
 
Mathematics news on Phys.org
Well, I don't think so.
Reason?
It ought to be just an artefact of the particular number representation system you use.

If you let "11" be your base number, rather than 10, your "23" will be written as 21, the latter digit not being prime at all.

The quality of a number being prime is independent of its particular representation, but you can't expext the same for the digits of two distinct representations of the same number.
 
I know that a prime number doesn't depend on its representation, but number theorists have names for different types of primes i.e. Mersenne primes, Irregular primes, Safe primes, and my personal favorite, Sexy primes. I just wanted to know if there was a name for this particular type of prime. For example, as you probably well know there is a name for numbers like 222. They're called palindromic numbers. Now, 313 is a palindromic number but it is also prime. I know that 313 is prime independently of being a palindromic number. That's just a coincidence. My point is, is there a specific name for primes whose digits are all prime? That's all I'm getting at. This also raises the question, are there an infinite number of palindromic primes? Maybe, for the sake of precision, I should have posed my question this way: In a base 10 number system is there a name for a prime number whose digits are all prime?
 
Mersenne primes are Mersenne primes in all number systems, and so on.

Sure, some of dubbed palindromic numbers as being palindromic. But, just because you set a name on something doesn't mean it constitutes anything worthwhile studying (i.e, nobody studies palindromic numbers)

The reason why palindromic numbers have gotten their name is that the property of palindromy is well known outside maths, so it sort of stuck.

I would be extremely surprised if anyone has given your types of perfectly definable numbers a particular name (I'm not at all saying your question was vague or anything. It wasn't, your first post was perfectly clear)
 
If you count 1 as not being prime, then numbers of this type can't exist in binary. The larger your base is, the more such numbers can exist in that base, because you have more single digit primes. Example, in Hex, B and D are prime. (Funny, I always thought of them as being "even letters".)

This sounds like "Happy numbers" which are also base dependent.
 
arildno said:
Mersenne primes are Mersenne primes in all number systems, and so on.

Sure, some of dubbed palindromic numbers as being palindromic. But, just because you set a name on something doesn't mean it constitutes anything worthwhile studying (i.e, nobody studies palindromic numbers)

The reason why palindromic numbers have gotten their name is that the property of palindromy is well known outside maths, so it sort of stuck.

I would be extremely surprised if anyone has given your types of perfectly definable numbers a particular name (I'm not at all saying your question was vague or anything. It wasn't, your first post was perfectly clear)

Then I think I will name them Digital Primes.
 

Similar threads

  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 8 ·
Replies
8
Views
1K
  • · Replies 17 ·
Replies
17
Views
2K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 4 ·
Replies
4
Views
3K