555

Here are quick math notes on the number 555. Let me know if you want a practice problem or a deeper dive into any part.

• Decimal: 555
• Prime factorization: 555 = 3 × 5 × 37
• Divisibility: divisible by 3 (sum of digits = 15), divisible by 5; not divisible by 9 (sum ≠ 0 mod 9)
• Number of divisors: (1+1)(1+1)(1+1) = 8
  • Divisors: 1, 3, 5, 15, 37, 111, 185, 555
• Sum of all divisors: (1+3)(1+5)(1+37) = 4 × 6 × 38 = 912
  • Sum of proper divisors (excluding 555): 912 − 555 = 357
• Roman numeral: DLV
• Base representations:
  • Binary: 1000101011_2
  • Octal: 1053_8
  • Hexadecimal: 0x22B
  • Base 7: 1422_7
  • Base 6: 2323_6

Would you like a quick practice problem using 555, or a deeper look at any of these conversions?