The number 18120
18120 is a composite number with 32 divisors. Its prime factorisation is × 3 × 5 × 151. Divisors (32): 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120 … 18120.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 18120: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 12.
- 2
18120 is composite. Its prime factorisation is
- 3
The divisors add up to 54720; without 18120 itself that is 36600, so 18120 is abundant (36600 is more than 18120). Euler's totient φ(18120) = 4800 numbers up to 18120 share no factor with it.
- 4
The digits of 18120 add up to 12, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 66 steps to reach 1.
LaTeX source of the formulas on this page
\[ 18120 = 2^{3} \times 3 \times 5 \times 151 \]18120 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 32 |
| Sum of divisors | 54720 |
| Euler totient φ(n) | 4800 |
| Square | 328334400 |
| Cube | 5949419328000 |
| Square root | 134.610549 (= 2√4530) |
| Digit sum / digital root | 12 / 3 |
| Collatz steps to 1 | 66 |
| Scientific notation | 1.812 × |
18120 in other forms
| Form | Value |
|---|---|
| In words | eighteen thousand one hundred and twenty |
| Binary (base 2) | 100011011001000 |
| Octal (base 8) | 43310 |
| Hexadecimal (base 16) | 46C8 |
| Base 3 | 220212010 |
| As time | 18120 seconds = 5 h 2 min 0 s |
Is 18120 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (18120 ÷ 2 = 9060) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (18120 ÷ 3 = 6040) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (18120 ÷ 4 = 4530) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (18120 ÷ 5 = 3624) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (18120 ÷ 6 = 3020) | 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 | Yes (18120 ÷ 8 = 2265) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (18120 ÷ 10 = 1812) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | Yes (18120 ÷ 12 = 1510) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 18120 a prime number?
No. 18120 = × 3 × 5 × 151, so it is divisible by 2.
What are the factors of 18120?
1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120, 151, 302, 453, 604, 755, 906, 1208, 1510, 1812, 2265, 3020, 3624, 4530, 6040, 9060, 18120.
What is 18120 in binary?
100011011001000 (hexadecimal 46C8, octal 43310).
What is the square root of 18120?
About 134.6105, exactly 2√4530.
Is 18120 divisible by 3?
Yes. Its digits add up to 12, a multiple of 3.
What is special about the number 18120?
18120 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 12.