555

Not sure what you want about 555. Do you want math facts, or something else (electronics, roman numerals, etc.)? Here are quick math-focused notes you can use for exam prep:

• Prime factorization: 555 = 3 × 5 × 37
• Divisibility: divisible by 3, 5, and 15; not by 9 or 11
• Number of divisors: 8 (1, 3, 5, 15, 37, 111, 185, 555)
• Sum of divisors: 912; sum of proper divisors = 912 − 555 = 357
• Representations:
  • Binary: 1000101011
  • Hexadecimal: 0x22B
  • Octal: 1053
  • Roman numeral: DLV

Sample exam-style problems (quick Practice):

• Factor 555 and list all divisors.
• Compute 555 mod 7.
• If a product costs 555 dollars and you pay 8% sales tax, what is the total price you pay?
• Find the sum of all divisors of 555.

If you meant something else (555 timer IC, or another context), tell me the area and I’ll tailor questions or explanations.