I am a prime number less than 100. My digits add to 13. What number am I?

67

Because 6+7=13

To find the prime number that satisfies the given conditions, we need to check each prime number less than 100 and find the one whose digits add up to 13.

Let's start by listing out the prime numbers less than 100: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, and 97.

Now, let's calculate the sum of the digits for each of these prime numbers:

2: 2
3: 3
5: 5
7: 7
11: 1 + 1 = 2
13: 1 + 3 = 4
17: 1 + 7 = 8
19: 1 + 9 = 10
23: 2 + 3 = 5
29: 2 + 9 = 11
31: 3 + 1 = 4
37: 3 + 7 = 10
41: 4 + 1 = 5
43: 4 + 3 = 7
47: 4 + 7 = 11
53: 5 + 3 = 8
59: 5 + 9 = 14
61: 6 + 1 = 7
67: 6 + 7 = 13 (This is our answer!)

Therefore, the prime number less than 100 whose digits add up to 13 is 67.

97?

You'll find it on this chart.

http://www.scsb.org/trh/prime/100_sieve_finished.png