The number 81374
81374 is a composite number with 16 divisors. Its prime factorisation is 2 × 23 × 29 × 61. Divisors (16): 1, 2, 23, 29, 46, 58, 61, 122, 667, 1334, 1403, 1769, 2806, 3538, 40687, 81374.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 81374: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 23.
- 2
81374 is composite. Its prime factorisation is
- 3
The divisors add up to 133920; without 81374 itself that is 52546, so 81374 is deficient (52546 is less than 81374). Euler's totient φ(81374) = 36960 numbers up to 81374 share no factor with it.
- 4
The digits of 81374 add up to 23, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 182 steps to reach 1.
LaTeX source of the formulas on this page
\[ 81374 = 2 \times 23 \times 29 \times 61 \]
81374 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 133920 |
| Euler totient φ(n) | 36960 |
| Square | 6621727876 |
| Cube | 538836484181624 |
| Square root | 285.261284 |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 182 |
| Scientific notation | 8.1374 × |
81374 in other forms
| Form | Value |
|---|---|
| In words | eighty-one thousand three hundred and seventy-four |
| Binary (base 2) | 10011110111011110 |
| Octal (base 8) | 236736 |
| Hexadecimal (base 16) | 13DDE |
| Base 3 | 11010121212 |
| As time | 81374 seconds = 22 h 36 min 14 s |
Is 81374 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (81374 ÷ 2 = 40687) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 2) | 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 | No (remainder 2) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 6) | 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 6) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 5) | 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 7) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 2) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 81374 a prime number?
No. 81374 = 2 × 23 × 29 × 61, so it is divisible by 2.
What are the factors of 81374?
1, 2, 23, 29, 46, 58, 61, 122, 667, 1334, 1403, 1769, 2806, 3538, 40687, 81374.
What is 81374 in binary?
10011110111011110 (hexadecimal 13DDE, octal 236736).
What is the square root of 81374?
About 285.2613.
Is 81374 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 81374?
81374 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 23.