212
CCXII
11010100
The number 212 — factors and divisors
Deficient
212 = 2² × 53. It has 6 divisors, adding up to 378.
Its divisors, itself excluded, add up to less than the number.
Laid out as dots
It fits as 4 × 53. The more divisors, the closer to a square.
- Prime factors
- 2² × 53
- Divisors
- 1, 2, 4, 53, 106, 212
- Sum of divisors
- 378
- Sum without itself
- 166
- Coprime below it
- 104
- Digit sum
- 5
- Digital root
- 5
- Roman numeral
- CCXII
- Binary
- 11010100
- Octal
- 324
- Hexadecimal
- D4
- Base 36
- 5W
- Bits
- 8 bits
- Collatz steps
- 13 steps · peaks at 212
- Prime before
- 211
- Prime after
- 223
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 212 a prime number?
No. It breaks down into 2² × 53.
Q. What are the divisors of 212?
1, 2, 4, 53, 106, 212 — 6 divisors in all, adding up to 378.
Q. How is 212 written in binary?
11010100, which is 8 bits. In hexadecimal it is D4.
Q. How many Collatz steps does 212 take?
It reaches 1 in 13, peaking at 212 on the way.