The number 72018
72018 is a composite number with 12 divisors. Its prime factorisation is 2 × × 4001. Divisors (12): 1, 2, 3, 6, 9, 18, 4001, 8002, 12003, 24006, 36009, 72018.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 72018: a Harshad number: divisible by its digit sum 18.
- 2
72018 is composite. Its prime factorisation is
- 3
The divisors add up to 156078; without 72018 itself that is 84060, so 72018 is abundant (84060 is more than 72018). Euler's totient φ(72018) = 24000 numbers up to 72018 share no factor with it.
- 4
The digits of 72018 add up to 18, and repeating that until one digit is left gives the digital root 9. The Collatz sequence (halve if even, else 3n+1) takes 179 steps to reach 1.
LaTeX source of the formulas on this page
\[ 72018 = 2 \times 3^{2} \times 4001 \]72018 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 12 |
| Sum of divisors | 156078 |
| Euler totient φ(n) | 24000 |
| Square | 5186592324 |
| Cube | 373528005989832 |
| Square root | 268.361696 (= 3√8002) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 179 |
| Scientific notation | 7.2018 × |
72018 in other forms
| Form | Value |
|---|---|
| In words | seventy-two thousand and eighteen |
| Binary (base 2) | 10001100101010010 |
| Octal (base 8) | 214522 |
| Hexadecimal (base 16) | 11952 |
| Base 3 | 10122210100 |
| As time | 72018 seconds = 20 h 0 min 18 s |
Is 72018 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (72018 ÷ 2 = 36009) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (72018 ÷ 3 = 24006) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (72018 ÷ 6 = 12003) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 2) | 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 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (72018 ÷ 9 = 8002) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 8) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 1) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 6) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 72018 a prime number?
No. 72018 = 2 × × 4001, so it is divisible by 2.
What are the factors of 72018?
1, 2, 3, 6, 9, 18, 4001, 8002, 12003, 24006, 36009, 72018.
What is 72018 in binary?
10001100101010010 (hexadecimal 11952, octal 214522).
What is the square root of 72018?
About 268.3617, exactly 3√8002.
Is 72018 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 72018?
72018 is a Harshad number: divisible by its digit sum 18.