// Define a function to check if a number is prime
function isPrime(n):
    if n <= 1:
        return False
    for i from 2 to n-1:
        if n % i == 0:
            return False
    return True

// Loop through all 3-digit numbers starting with 5
for num from 500 to 599:
    // Check if the number is prime and has 3 digits
    if isPrime(num) and len(str(num)) == 3:
        // Display the prime number
        print(num)