555

Not sure what you mean by 555. Do you mean:

• The number 555 (math questions)?
• The 555 timer IC (electronics)?
• The Thai/Internet slang 555 (means haha)?

If you want math practice, here are quick facts and a mini-quiz you can try:

Quick facts about 555 (decimal):

• Prime factorization: 555 = 3 × 5 × 37
• Divisible by: 3, 5, 15, 37, 111, 185, 555
• Roman numeral: DLV
• Binary: 1000101011
• Hexadecimal: 0x22B

Mini-quiz (5 questions):

1. Factorize 555 completely.
2. Convert 555 to binary (done above, but show your steps).
3. Convert 555 to hexadecimal.
4. Is 555 divisible by 7? Why or why not?
5. Sum of digits is 15. Is 555 divisible by 9? Why?

If you meant something else (555 timer or the Thai slang), tell me which topic and I’ll tailor a quick study guide or practice questions.