159
CLIX
10011111
The number 159 — factors and divisors
Deficient
159 = 3 × 53. It has 4 divisors, adding up to 216.
Its divisors, itself excluded, add up to less than the number.
Laid out as dots
It fits as 3 × 53. The more divisors, the closer to a square.
- Prime factors
- 3 × 53
- Divisors
- 1, 3, 53, 159
- Sum of divisors
- 216
- Sum without itself
- 57
- Coprime below it
- 104
- Digit sum
- 15
- Digital root
- 6
- Roman numeral
- CLIX
- Binary
- 10011111
- Octal
- 237
- Hexadecimal
- 9F
- Base 36
- 4F
- Bits
- 8 bits
- Collatz steps
- 54 steps · peaks at 9,232
- Prime before
- 157
- Prime after
- 163
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 159 a prime number?
No. It breaks down into 3 × 53.
Q. What are the divisors of 159?
1, 3, 53, 159 — 4 divisors in all, adding up to 216.
Q. How is 159 written in binary?
10011111, which is 8 bits. In hexadecimal it is 9F.
Q. How many Collatz steps does 159 take?
It reaches 1 in 54, peaking at 9,232 on the way.