Three
They are ;- 41,43, & 47
Any number ending is '4' is NOT a Prime number, because it is an EVEn number, divisible by '2'.
There are 5460 five digit numbers with a digit sum of 22.
There is no simple formula for that; I suggest you look up the prime numbers in a table of prime numbers, analyzing each prime number in the range 10-99 whether it fulfills this specific criterion.
There are 60480 numbers.
To find the even two-digit numbers where the sum of the digits is 5, we need to consider the possible combinations of digits. The digits that sum up to 5 are (1,4) and (2,3). For the numbers to be even, the units digit must be 4, so the possible numbers are 14 and 34. Therefore, there are 2 even two-digit numbers where the sum of the digits is 5.
There are 5760 such numbers.
there are 4
61 42 56 89
There are 21 two-digit prime numbers.
With 123 digits you can make 123 one-digit numbers.
There are 5460 five digit numbers with a digit sum of 22.
27 three digit numbers from the digits 3, 5, 7 including repetitions.
3 41 43 47
5040 different 4 digit numbers can be formed with the digits 123456789. This is assuming that no digits are repeated with each combination.
There is no simple formula for that; I suggest you look up the prime numbers in a table of prime numbers, analyzing each prime number in the range 10-99 whether it fulfills this specific criterion.
757
There are 90000 5-digit numbers.
7 two-digit numbers.