555

Could you clarify what you want with "555"? Here are a few quick math-related things about the number 555 you could use for exam prep. Pick one or tell me a topic and I’ll tailor problems.

• Prime factorization: 555 = 3 × 5 × 37
• Divisors: 1, 3, 5, 15, 37, 111, 185, 555
• Sum of divisors (σ(555)): 912
• Euler’s totient: φ(555) = 288
• Binary representation: 555 = 1000101011₂
• Base-8 (octal) representation: 555₁₀ = 0o? (if you want, I can convert)
• A quick congruence check: 555 mod n for any n you choose

If you’d like, I can turn this into a short practice set (with steps) or apply 555 to a specific topic (e.g., modular arithmetic, divisors, or bases). Which would you prefer?