68
LXVIII
1000100
The number 68 — factors and divisors
Deficient
68 = 2² × 17. It has 6 divisors, adding up to 126.
Its divisors, itself excluded, add up to less than the number.
Laid out as dots
It fits as 4 × 17. The more divisors, the closer to a square.
- Prime factors
- 2² × 17
- Divisors
- 1, 2, 4, 17, 34, 68
- Sum of divisors
- 126
- Sum without itself
- 58
- Coprime below it
- 32
- Digit sum
- 14
- Digital root
- 5
- Roman numeral
- LXVIII
- Binary
- 1000100
- Octal
- 104
- Hexadecimal
- 44
- Base 36
- 1W
- Bits
- 7 bits
- Collatz steps
- 14 steps · peaks at 68
- Prime before
- 67
- Prime after
- 71
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 68 a prime number?
No. It breaks down into 2² × 17.
Q. What are the divisors of 68?
1, 2, 4, 17, 34, 68 — 6 divisors in all, adding up to 126.
Q. How is 68 written in binary?
1000100, which is 7 bits. In hexadecimal it is 44.
Q. How many Collatz steps does 68 take?
It reaches 1 in 14, peaking at 68 on the way.