Numbers·163
163
CLXIII
10100011

The number 163 — factors and divisors

Deficient

163 is a prime: only 1 and itself divide it. The prime before is 157, the next is 167.

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

Families it belongs to

Prime

Nothing divides it but 1 and itself.

Laid out as dots

It only fits in one row. Having no other rectangle is what being prime means.

Prime factors
It does not break down further
Divisors
1, 163
Sum of divisors
164
Sum without itself
1
Coprime below it
162
Digit sum
10
Digital root
1
Roman numeral
CLXIII
Binary
10100011
Octal
243
Hexadecimal
A3
Base 36
4J
Bits
8 bits
Collatz steps
23 steps · peaks at 736
Prime before
157
Prime after
167

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 163 a prime number?

Yes. Nothing divides it but 1 and itself.

Q. What are the divisors of 163?

1, 163 — 2 divisors in all, adding up to 164.

Q. How is 163 written in binary?

10100011, which is 8 bits. In hexadecimal it is A3.

Q. How many Collatz steps does 163 take?

It reaches 1 in 23, peaking at 736 on the way.