228
CCXXVIII
11100100
The number 228 — factors and divisors
Abundant
228 = 2² × 3 × 19. It has 12 divisors, adding up to 560.
Its divisors, itself excluded, add up to more than the number.
Laid out as dots
It fits as 12 × 19. The more divisors, the closer to a square.
- Prime factors
- 2² × 3 × 19
- Divisors
- 1, 2, 3, 4, 6, 12, 19, 38, 57, 76, 114, 228
- Sum of divisors
- 560
- Sum without itself
- 332
- Coprime below it
- 72
- Digit sum
- 12
- Digital root
- 3
- Roman numeral
- CCXXVIII
- Binary
- 11100100
- Octal
- 344
- Hexadecimal
- E4
- Base 36
- 6C
- Bits
- 8 bits
- Collatz steps
- 34 steps · peaks at 228
- Prime before
- 227
- Prime after
- 229
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 228 a prime number?
No. It breaks down into 2² × 3 × 19.
Q. What are the divisors of 228?
1, 2, 3, 4, 6, 12, 19, 38, 57, 76, 114, 228 — 12 divisors in all, adding up to 560.
Q. How is 228 written in binary?
11100100, which is 8 bits. In hexadecimal it is E4.
Q. How many Collatz steps does 228 take?
It reaches 1 in 34, peaking at 228 on the way.