The number 4015
4015 is a composite number with 8 divisors. Its prime factorisation is 5 × 11 × 73. Divisors (8): 1, 5, 11, 55, 73, 365, 803, 4015.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
4015 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
4015 is composite. Its prime factorisation is
- 3
The divisors add up to 5328; without 4015 itself that is 1313, so 4015 is deficient (1313 is less than 4015). Euler's totient φ(4015) = 2880 numbers up to 4015 share no factor with it.
- 4
The digits of 4015 add up to 10, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 43 steps to reach 1.
LaTeX source of the formulas on this page
\[ 4015 = 5 \times 11 \times 73 \]
4015 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 5328 |
| Euler totient φ(n) | 2880 |
| Square | 16120225 |
| Cube | 64722703375 |
| Square root | 63.364028 |
| Digit sum / digital root | 10 / 1 |
| Collatz steps to 1 | 43 |
| Scientific notation | 4.015 × |
4015 in other forms
| Form | Value |
|---|---|
| In words | four thousand and fifteen |
| Binary (base 2) | 111110101111 |
| Octal (base 8) | 7657 |
| Hexadecimal (base 16) | FAF |
| Base 3 | 12111201 |
| As time | 4015 seconds = 1 h 6 min 55 s |
Is 4015 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (4015 ÷ 5 = 803) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 1) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 4) | A number is divisible by 7 if double the last digit and subtract it from the rest: the result is a multiple of 7. |
| 8 | No (remainder 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 5) | A number is divisible by 10 if the last digit is 0. |
| 11 | Yes (4015 ÷ 11 = 365) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 7) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 4015 a prime number?
No. 4015 = 5 × 11 × 73, so it is divisible by 5.
What are the factors of 4015?
1, 5, 11, 55, 73, 365, 803, 4015.
What is 4015 in binary?
111110101111 (hexadecimal FAF, octal 7657).
What is the square root of 4015?
About 63.3640.
Is 4015 divisible by 3?
No. Its digits add up to 10, which is not a multiple of 3.
What is special about the number 4015?
It is a composite number with 8 divisors.