143
CXLIII
10001111
The number 143 — factors and divisors
Deficient
143 = 11 × 13. It has 4 divisors, adding up to 168.
Its divisors, itself excluded, add up to less than the number.
Laid out as dots
It fits as 11 × 13. The more divisors, the closer to a square.
- Prime factors
- 11 × 13
- Divisors
- 1, 11, 13, 143
- Sum of divisors
- 168
- Sum without itself
- 25
- Coprime below it
- 120
- Digit sum
- 8
- Digital root
- 8
- Roman numeral
- CXLIII
- Binary
- 10001111
- Octal
- 217
- Hexadecimal
- 8F
- Base 36
- 3Z
- Bits
- 8 bits
- Collatz steps
- 103 steps · peaks at 9,232
- Prime before
- 139
- Prime after
- 149
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 143 a prime number?
No. It breaks down into 11 × 13.
Q. What are the divisors of 143?
1, 11, 13, 143 — 4 divisors in all, adding up to 168.
Q. How is 143 written in binary?
10001111, which is 8 bits. In hexadecimal it is 8F.
Q. How many Collatz steps does 143 take?
It reaches 1 in 103, peaking at 9,232 on the way.