207
CCVII
11001111
The number 207 — factors and divisors
Deficient
207 = 3² × 23. It has 6 divisors, adding up to 312.
Its divisors, itself excluded, add up to less than the number.
Laid out as dots
It fits as 9 × 23. The more divisors, the closer to a square.
- Prime factors
- 3² × 23
- Divisors
- 1, 3, 9, 23, 69, 207
- Sum of divisors
- 312
- Sum without itself
- 105
- Coprime below it
- 132
- Digit sum
- 9
- Digital root
- 9
- Roman numeral
- CCVII
- Binary
- 11001111
- Octal
- 317
- Hexadecimal
- CF
- Base 36
- 5R
- Bits
- 8 bits
- Collatz steps
- 88 steps · peaks at 9,232
- Prime before
- 199
- Prime after
- 211
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 207 a prime number?
No. It breaks down into 3² × 23.
Q. What are the divisors of 207?
1, 3, 9, 23, 69, 207 — 6 divisors in all, adding up to 312.
Q. How is 207 written in binary?
11001111, which is 8 bits. In hexadecimal it is CF.
Q. How many Collatz steps does 207 take?
It reaches 1 in 88, peaking at 9,232 on the way.