Numbers·187
187
CLXXXVII
10111011

The number 187 — factors and divisors

Deficient

187 = 11 × 17. It has 4 divisors, adding up to 216.

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

Laid out as dots

It fits as 11 × 17. The more divisors, the closer to a square.

Prime factors
11 × 17
Divisors
1, 11, 17, 187
Sum of divisors
216
Sum without itself
29
Coprime below it
160
Digit sum
16
Digital root
7
Roman numeral
CLXXXVII
Binary
10111011
Octal
273
Hexadecimal
BB
Base 36
57
Bits
8 bits
Collatz steps
44 steps · peaks at 952
Prime before
181
Prime after
191

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 187 a prime number?

No. It breaks down into 11 × 17.

Q. What are the divisors of 187?

1, 11, 17, 187 — 4 divisors in all, adding up to 216.

Q. How is 187 written in binary?

10111011, which is 8 bits. In hexadecimal it is BB.

Q. How many Collatz steps does 187 take?

It reaches 1 in 44, peaking at 952 on the way.