180
CLXXX
10110100
The number 180 — factors and divisors
Abundant
180 = 2² × 3² × 5. It has 18 divisors, adding up to 546.
Its divisors, itself excluded, add up to more than the number.
Laid out as dots
It fits as 12 × 15. The more divisors, the closer to a square.
- Prime factors
- 2² × 3² × 5
- Divisors
- 1, 2, 3, 4, 5, 6, 9, 10, 12, 15, 18, 20, 30, 36, 45, 60, 90, 180
- Sum of divisors
- 546
- Sum without itself
- 366
- Coprime below it
- 48
- Digit sum
- 9
- Digital root
- 9
- Roman numeral
- CLXXX
- Binary
- 10110100
- Octal
- 264
- Hexadecimal
- B4
- Base 36
- 50
- Bits
- 8 bits
- Collatz steps
- 18 steps · peaks at 180
- Prime before
- 179
- Prime after
- 181
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 180 a prime number?
No. It breaks down into 2² × 3² × 5.
Q. What are the divisors of 180?
1, 2, 3, 4, 5, 6, 9, 10, 12, 15, 18, 20, 30, 36, 45, 60, 90, 180 — 18 divisors in all, adding up to 546.
Q. How is 180 written in binary?
10110100, which is 8 bits. In hexadecimal it is B4.
Q. How many Collatz steps does 180 take?
It reaches 1 in 18, peaking at 180 on the way.