140
CXL
10001100
The number 140 — factors and divisors
Abundant
140 = 2² × 5 × 7. It has 12 divisors, adding up to 336.
Its divisors, itself excluded, add up to more than the number.
Laid out as dots
It fits as 10 × 14. The more divisors, the closer to a square.
- Prime factors
- 2² × 5 × 7
- Divisors
- 1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 70, 140
- Sum of divisors
- 336
- Sum without itself
- 196
- Coprime below it
- 48
- Digit sum
- 5
- Digital root
- 5
- Roman numeral
- CXL
- Binary
- 10001100
- Octal
- 214
- Hexadecimal
- 8C
- Base 36
- 3W
- Bits
- 8 bits
- Collatz steps
- 15 steps · peaks at 160
- 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 140 a prime number?
No. It breaks down into 2² × 5 × 7.
Q. What are the divisors of 140?
1, 2, 4, 5, 7, 10, 14, 20, 28, 35, 70, 140 — 12 divisors in all, adding up to 336.
Q. How is 140 written in binary?
10001100, which is 8 bits. In hexadecimal it is 8C.
Q. How many Collatz steps does 140 take?
It reaches 1 in 15, peaking at 160 on the way.