The number 81464
81464 is a composite number with 16 divisors. Its prime factorisation is × 17 × 599. Divisors (16): 1, 2, 4, 8, 17, 34, 68, 136, 599, 1198, 2396, 4792, 10183, 20366, 40732, 81464.
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How to work it out
- 1
What is special about 81464: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
81464 is composite. Its prime factorisation is
- 3
The divisors add up to 162000; without 81464 itself that is 80536, so 81464 is deficient (80536 is less than 81464). Euler's totient φ(81464) = 38272 numbers up to 81464 share no factor with it.
- 4
The digits of 81464 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 89 steps to reach 1.
LaTeX source of the formulas on this page
\[ 81464 = 2^{3} \times 17 \times 599 \]81464 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 162000 |
| Euler totient φ(n) | 38272 |
| Square | 6636383296 |
| Cube | 540626328825344 |
| Square root | 285.418990 (= 2√20366) |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 89 |
| Scientific notation | 8.1464 × |
81464 in other forms
| Form | Value |
|---|---|
| In words | eighty-one thousand four hundred and sixty-four |
| Binary (base 2) | 10011111000111000 |
| Octal (base 8) | 237070 |
| Hexadecimal (base 16) | 13E38 |
| Base 3 | 11010202012 |
| As time | 81464 seconds = 22 h 37 min 44 s |
Is 81464 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (81464 ÷ 2 = 40732) | 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 | Yes (81464 ÷ 4 = 20366) | 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 5) | 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 (81464 ÷ 8 = 10183) | 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 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 8) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 81464 a prime number?
No. 81464 = × 17 × 599, so it is divisible by 2.
What are the factors of 81464?
1, 2, 4, 8, 17, 34, 68, 136, 599, 1198, 2396, 4792, 10183, 20366, 40732, 81464.
What is 81464 in binary?
10011111000111000 (hexadecimal 13E38, octal 237070).
What is the square root of 81464?
About 285.4190, exactly 2√20366.
Is 81464 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 81464?
81464 is a happy number: repeatedly adding the squares of its digits reaches 1.