The number 18880
18880 is a composite number with 28 divisors. Its prime factorisation is × 5 × 59. Divisors (28): 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 59, 64, 80, 118, 160, 236 … 18880.
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How to work it out
- 1
What is special about 18880: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
18880 is composite. Its prime factorisation is
- 3
The divisors add up to 45720; without 18880 itself that is 26840, so 18880 is abundant (26840 is more than 18880). Euler's totient φ(18880) = 7424 numbers up to 18880 share no factor with it.
- 4
The digits of 18880 add up to 25, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 61 steps to reach 1.
LaTeX source of the formulas on this page
\[ 18880 = 2^{6} \times 5 \times 59 \]18880 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 28 |
| Sum of divisors | 45720 |
| Euler totient φ(n) | 7424 |
| Square | 356454400 |
| Cube | 6729859072000 |
| Square root | 137.404512 (= 8√295) |
| Digit sum / digital root | 25 / 7 |
| Collatz steps to 1 | 61 |
| Scientific notation | 1.888 × |
18880 in other forms
| Form | Value |
|---|---|
| In words | eighteen thousand eight hundred and eighty |
| Binary (base 2) | 100100111000000 |
| Octal (base 8) | 44700 |
| Hexadecimal (base 16) | 49C0 |
| Base 3 | 221220021 |
| As time | 18880 seconds = 5 h 14 min 40 s |
Is 18880 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (18880 ÷ 2 = 9440) | 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 | Yes (18880 ÷ 4 = 4720) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (18880 ÷ 5 = 3776) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 1) | 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 (18880 ÷ 8 = 2360) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 7) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (18880 ÷ 10 = 1888) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 4) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 4) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 18880 a prime number?
No. 18880 = × 5 × 59, so it is divisible by 2.
What are the factors of 18880?
1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 59, 64, 80, 118, 160, 236, 295, 320, 472, 590, 944, 1180, 1888, 2360, 3776, 4720, 9440, 18880.
What is 18880 in binary?
100100111000000 (hexadecimal 49C0, octal 44700).
What is the square root of 18880?
About 137.4045, exactly 8√295.
Is 18880 divisible by 3?
No. Its digits add up to 25, which is not a multiple of 3.
What is special about the number 18880?
18880 is a happy number: repeatedly adding the squares of its digits reaches 1.