The number 29820
29820 is a composite number with 48 divisors. Its prime factorisation is × 3 × 5 × 7 × 71. Divisors (48): 1, 2, 3, 4, 5, 6, 7, 10, 12, 14, 15, 20, 21, 28, 30, 35 … 29820.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 29820: a Harshad number: divisible by its digit sum 21.
- 2
29820 is composite. Its prime factorisation is
- 3
The divisors add up to 96768; without 29820 itself that is 66948, so 29820 is abundant (66948 is more than 29820). Euler's totient φ(29820) = 6720 numbers up to 29820 share no factor with it.
- 4
The digits of 29820 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 72 steps to reach 1.
LaTeX source of the formulas on this page
\[ 29820 = 2^{2} \times 3 \times 5 \times 7 \times 71 \]29820 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 48 |
| Sum of divisors | 96768 |
| Euler totient φ(n) | 6720 |
| Square | 889232400 |
| Cube | 26516910168000 |
| Square root | 172.684684 (= 2√7455) |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 72 |
| Scientific notation | 2.982 × |
29820 in other forms
| Form | Value |
|---|---|
| In words | twenty-nine thousand eight hundred and twenty |
| Binary (base 2) | 111010001111100 |
| Octal (base 8) | 72174 |
| Hexadecimal (base 16) | 747C |
| Base 3 | 1111220110 |
| As time | 29820 seconds = 8 h 17 min 0 s |
Is 29820 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (29820 ÷ 2 = 14910) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (29820 ÷ 3 = 9940) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | Yes (29820 ÷ 4 = 7455) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (29820 ÷ 5 = 5964) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (29820 ÷ 6 = 4970) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (29820 ÷ 7 = 4260) | 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 4) | 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 (29820 ÷ 10 = 2982) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 10) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | Yes (29820 ÷ 12 = 2485) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 29820 a prime number?
No. 29820 = × 3 × 5 × 7 × 71, so it is divisible by 2.
What are the factors of 29820?
1, 2, 3, 4, 5, 6, 7, 10, 12, 14, 15, 20, 21, 28, 30, 35, 42, 60, 70, 71, 84, 105, 140, 142, 210, 213, 284, 355, 420, 426, 497, 710, 852, 994, 1065, 1420, 1491, 1988, 2130, 2485, 2982, 4260, 4970, 5964, 7455, 9940, 14910, 29820.
What is 29820 in binary?
111010001111100 (hexadecimal 747C, octal 72174).
What is the square root of 29820?
About 172.6847, exactly 2√7455.
Is 29820 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 29820?
29820 is a Harshad number: divisible by its digit sum 21.