You know that the odd digits have to be in the units places, and the evens in the tens place, so the general solution is:
80 + 60 + 40 + 20 + 9 + 7 + 3 + 1 = 220
The three-digit prime number that meets the given criteria is 373. This number is prime itself, with all its digits (3) being prime. Additionally, when considering the first two digits (37) and the last two digits (73) separately, both combinations also form prime numbers.
3 41 43 47
For the tens digit to be a prime number then it must equal 2, 3, 5 or 7. There are four 3-digit prime numbers that fit the above condition and also have the tens and units digits forming a 2-digit prime number. 131, 137, 173, 179. The person supplying the question may like to sum the various combinations.
No, reversing the order of the digits of a two-digit prime number does not always result in a prime number.
Try different numbers who have a sum of digits equal to 11:38: Not a prime.29: This is a prime.Starting with 1: The other digit would have to be 10, so there are no further options.29.
73 is the largest two-digit number that is prime and has prime numbers for both of its digits.
73 is the largest 2 digit number that is both prime and has prime numbers for both of its digits.
You had me until "product." The product of 4 digits can't be prime.
Two-digit prime numbers whose digits add up to 10 are:193773
there are 4
Smallest is 11 & Largest is 77.
It would probably refer to a digit that is a prime number, or a composite number. Note that mathematicians normally talk about prime and composite NUMBERS, not individual digits.
73 satisfies your condition.
Any prime numbers of about 66 or 67 digits will do.
Any two prime numbers, of about 200 digits each, would work.Any two prime numbers, of about 200 digits each, would work.Any two prime numbers, of about 200 digits each, would work.Any two prime numbers, of about 200 digits each, would work.
The smallest two-digit prime number whose digits themselves are prime is 23. Both 2 and 3 are prime numbers, and together they form the prime number 23.
The smallest prime number in which all of the digits are also prime is 2.The smallest multi-digit prime number in which all of the digits are also prime is 23.