198
CXCVIII
11000110
The number 198 — factors and divisors
Abundant
198 = 2 × 3² × 11. It has 12 divisors, adding up to 468.
Its divisors, itself excluded, add up to more than the number.
Laid out as dots
It fits as 11 × 18. The more divisors, the closer to a square.
- Prime factors
- 2 × 3² × 11
- Divisors
- 1, 2, 3, 6, 9, 11, 18, 22, 33, 66, 99, 198
- Sum of divisors
- 468
- Sum without itself
- 270
- Coprime below it
- 60
- Digit sum
- 18
- Digital root
- 9
- Roman numeral
- CXCVIII
- Binary
- 11000110
- Octal
- 306
- Hexadecimal
- C6
- Base 36
- 5I
- Bits
- 8 bits
- Collatz steps
- 26 steps · peaks at 448
- Prime before
- 197
- Prime after
- 199
The grid
Ten per row, twenty rows. The filled cells are primes — you can see the multiples of 2 and 5 drop out in columns.
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Numbers either side
How to read this
- The prime factors are what the number is made of. The count and sum of divisors both follow from them.
- Add the divisors, take the number away, and you get perfect, abundant or deficient.
- The length of the binary form is the bit count. 255 taking eight digits is what a byte is.
- Collatz: halve it if even, triple it and add one if odd. The count is how many moves reach 1.
Frequently asked questions
Q. Is 198 a prime number?
No. It breaks down into 2 × 3² × 11.
Q. What are the divisors of 198?
1, 2, 3, 6, 9, 11, 18, 22, 33, 66, 99, 198 — 12 divisors in all, adding up to 468.
Q. How is 198 written in binary?
11000110, which is 8 bits. In hexadecimal it is C6.
Q. How many Collatz steps does 198 take?
It reaches 1 in 26, peaking at 448 on the way.