115
CXV
1110011
The number 115 — factors and divisors
Deficient
115 = 5 × 23. It has 4 divisors, adding up to 144.
Its divisors, itself excluded, add up to less than the number.
Laid out as dots
It fits as 5 × 23. The more divisors, the closer to a square.
- Prime factors
- 5 × 23
- Divisors
- 1, 5, 23, 115
- Sum of divisors
- 144
- Sum without itself
- 29
- Coprime below it
- 88
- Digit sum
- 7
- Digital root
- 7
- Roman numeral
- CXV
- Binary
- 1110011
- Octal
- 163
- Hexadecimal
- 73
- Base 36
- 37
- Bits
- 7 bits
- Collatz steps
- 33 steps · peaks at 520
- Prime before
- 113
- Prime after
- 127
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 115 a prime number?
No. It breaks down into 5 × 23.
Q. What are the divisors of 115?
1, 5, 23, 115 — 4 divisors in all, adding up to 144.
Q. How is 115 written in binary?
1110011, which is 7 bits. In hexadecimal it is 73.
Q. How many Collatz steps does 115 take?
It reaches 1 in 33, peaking at 520 on the way.