555

Not sure what you mean by 555. Here are a few common interpretations—tell me which one you’re after or provide more context:

• The number 555 (math): 555 = 3 × 5 × 37. It’s divisible by 3 and 5; sum of digits is 15; Roman numeral DLV. Number of divisors: 8.
• Roman numerals: 555 = DLV.
• 555 timer IC (electronics): a versatile timer IC used for oscillators and pulse generation (monostable/astable modes).
• 555 as laughter (Thai usage): “hahaha” (since 5 is pronounced “ha”).

If you’re studying for a specific course, tell me the subject and what you want to do with 555 (e.g., quick problems, explanations, conversions), and I’ll tailor it.