The number 81354
81354 is a composite number with 32 divisors. Its prime factorisation is 2 × 3 × 7 × 13 × 149. Divisors (32): 1, 2, 3, 6, 7, 13, 14, 21, 26, 39, 42, 78, 91, 149, 182, 273 … 81354.
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How to work it out
- 1
What is special about 81354: a Harshad number: divisible by its digit sum 21.
- 2
81354 is composite. Its prime factorisation is
- 3
The divisors add up to 201600; without 81354 itself that is 120246, so 81354 is abundant (120246 is more than 81354). Euler's totient φ(81354) = 21312 numbers up to 81354 share no factor with it.
- 4
The digits of 81354 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 89 steps to reach 1.
LaTeX source of the formulas on this page
\[ 81354 = 2 \times 3 \times 7 \times 13 \times 149 \]
81354 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 32 |
| Sum of divisors | 201600 |
| Euler totient φ(n) | 21312 |
| Square | 6618473316 |
| Cube | 538439278149864 |
| Square root | 285.226226 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 89 |
| Scientific notation | 8.1354 × |
81354 in other forms
| Form | Value |
|---|---|
| In words | eighty-one thousand three hundred and fifty-four |
| Binary (base 2) | 10011110111001010 |
| Octal (base 8) | 236712 |
| Hexadecimal (base 16) | 13DCA |
| Base 3 | 11010121010 |
| As time | 81354 seconds = 22 h 35 min 54 s |
Is 81354 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (81354 ÷ 2 = 40677) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (81354 ÷ 3 = 27118) | 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 4) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (81354 ÷ 6 = 13559) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (81354 ÷ 7 = 11622) | 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 | No (remainder 3) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 4) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | 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 81354 a prime number?
No. 81354 = 2 × 3 × 7 × 13 × 149, so it is divisible by 2.
What are the factors of 81354?
1, 2, 3, 6, 7, 13, 14, 21, 26, 39, 42, 78, 91, 149, 182, 273, 298, 447, 546, 894, 1043, 1937, 2086, 3129, 3874, 5811, 6258, 11622, 13559, 27118, 40677, 81354.
What is 81354 in binary?
10011110111001010 (hexadecimal 13DCA, octal 236712).
What is the square root of 81354?
About 285.2262.
Is 81354 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 81354?
81354 is a Harshad number: divisible by its digit sum 21.