The number 65520
65520 is a composite number with 120 divisors. Its prime factorisation is × × 5 × 7 × 13. Divisors (120): 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 18 … 65520.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 65520: a Harshad number: divisible by its digit sum 18.
- 2
65520 is composite. Its prime factorisation is
- 3
The divisors add up to 270816; without 65520 itself that is 205296, so 65520 is abundant (205296 is more than 65520). Euler's totient φ(65520) = 13824 numbers up to 65520 share no factor with it.
- 4
The digits of 65520 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 161 steps to reach 1.
LaTeX source of the formulas on this page
\[ 65520 = 2^{4} \times 3^{2} \times 5 \times 7 \times 13 \]65520 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 120 |
| Sum of divisors | 270816 |
| Euler totient φ(n) | 13824 |
| Square | 4292870400 |
| Cube | 281268868608000 |
| Square root | 255.968748 (= 12√455) |
| Digit sum / digital root | 18 / 9 |
| Collatz steps to 1 | 161 |
| Scientific notation | 6.552 × |
65520 in other forms
| Form | Value |
|---|---|
| In words | sixty-five thousand five hundred and twenty |
| Binary (base 2) | 1111111111110000 |
| Octal (base 8) | 177760 |
| Hexadecimal (base 16) | FFF0 |
| Base 3 | 10022212200 |
| As time | 65520 seconds = 18 h 12 min 0 s |
Is 65520 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (65520 ÷ 2 = 32760) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (65520 ÷ 3 = 21840) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (65520 ÷ 4 = 16380) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (65520 ÷ 5 = 13104) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (65520 ÷ 6 = 10920) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (65520 ÷ 7 = 9360) | 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 (65520 ÷ 8 = 8190) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | Yes (65520 ÷ 9 = 7280) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (65520 ÷ 10 = 6552) | 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 | Yes (65520 ÷ 12 = 5460) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 65520 a prime number?
No. 65520 = × × 5 × 7 × 13, so it is divisible by 2.
What are the factors of 65520?
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 18, 20, 21, 24, 26, 28, 30, 35, 36, 39, 40, 42, 45, 48, 52, 56, 60, 63, 65, 70, 72, 78, 80, 84, 90, 91, 104, 105, 112, 117, 120, 126, 130, 140, 144, 156, 168, 180, 182, 195, 208, 210, 234, 240, 252, 260, 273, 280, 312, 315, 336, 360, 364, 390, 420, 455, 468, 504, 520, 546, 560, 585, 624, 630, 720, 728, 780, 819, 840, 910, 936, 1008, 1040, 1092, 1170, 1260, 1365, 1456, 1560, 1638, 1680, 1820, 1872, 2184, 2340, 2520, 2730, 3120, 3276, 3640, 4095, 4368, 4680, 5040, 5460, 6552, 7280, 8190, 9360, 10920, 13104, 16380, 21840, 32760, 65520.
What is 65520 in binary?
1111111111110000 (hexadecimal FFF0, octal 177760).
What is the square root of 65520?
About 255.9687, exactly 12√455.
Is 65520 divisible by 3?
Yes. Its digits add up to 18, a multiple of 3.
What is special about the number 65520?
65520 is a Harshad number: divisible by its digit sum 18.