Numbers·111
111
CXI
1101111

The number 111 — factors and divisors

Deficient

111 = 3 × 37. It has 4 divisors, adding up to 152.

Its divisors, itself excluded, add up to less than the number.

Laid out as dots

It fits as 3 × 37. The more divisors, the closer to a square.

Prime factors
3 × 37
Divisors
1, 3, 37, 111
Sum of divisors
152
Sum without itself
41
Coprime below it
72
Digit sum
3
Digital root
3
Roman numeral
CXI
Binary
1101111
Octal
157
Hexadecimal
6F
Base 36
33
Bits
7 bits
Collatz steps
69 steps · peaks at 9,232
Prime before
109
Prime after
113

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.

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 111 a prime number?

No. It breaks down into 3 × 37.

Q. What are the divisors of 111?

1, 3, 37, 111 — 4 divisors in all, adding up to 152.

Q. How is 111 written in binary?

1101111, which is 7 bits. In hexadecimal it is 6F.

Q. How many Collatz steps does 111 take?

It reaches 1 in 69, peaking at 9,232 on the way.