555

Here are a few quick notes about the number 555 (handy for practice problems):

• Prime factorization: 555 = 3 × 5 × 37
• Divisors: 1, 3, 5, 15, 37, 111, 185, 555 (eight divisors)
• Sum of divisors: 912 (sum of proper divisors = 912 − 555 = 357)
• Is a Harshad (n is divisible by sum of its digits): 555 ÷ (5+5+5) = 555 ÷ 15 = 37
• It’s an odd composite number
• In Roman numerals: DLV

Would you like me to solve a quick problem with 555 (e.g., gcd/lcm with another number, or listing its divisors), or generate a short practice set based on your course? If you want, I can solve this example now: gcd(555, 420) and lcm(555, 420).