Numbers·63
63
LXIII
111111

The number 63 — factors and divisors

Deficient

63 = 3² × 7. It has 6 divisors, adding up to 104.

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

Laid out as dots

It fits as 7 × 9. The more divisors, the closer to a square.

Prime factors
3² × 7
Divisors
1, 3, 7, 9, 21, 63
Sum of divisors
104
Sum without itself
41
Coprime below it
36
Digit sum
9
Digital root
9
Roman numeral
LXIII
Binary
111111
Octal
77
Hexadecimal
3F
Base 36
1R
Bits
6 bits
Collatz steps
107 steps · peaks at 9,232
Prime before
61
Prime after
67

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 63 a prime number?

No. It breaks down into 3² × 7.

Q. What are the divisors of 63?

1, 3, 7, 9, 21, 63 — 6 divisors in all, adding up to 104.

Q. How is 63 written in binary?

111111, which is 6 bits. In hexadecimal it is 3F.

Q. How many Collatz steps does 63 take?

It reaches 1 in 107, peaking at 9,232 on the way.