The number 51801
51801 is a composite number with 8 divisors. Its prime factorisation is 3 × 31 × 557. Divisors (8): 1, 3, 31, 93, 557, 1671, 17267, 51801.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 51801: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
51801 is composite. Its prime factorisation is
- 3
The divisors add up to 71424; without 51801 itself that is 19623, so 51801 is deficient (19623 is less than 51801). Euler's totient φ(51801) = 33360 numbers up to 51801 share no factor with it.
- 4
The digits of 51801 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 65 steps to reach 1.
LaTeX source of the formulas on this page
\[ 51801 = 3 \times 31 \times 557 \]
51801 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 71424 |
| Euler totient φ(n) | 33360 |
| Square | 2683343601 |
| Cube | 138999881875401 |
| Square root | 227.598330 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 65 |
| Scientific notation | 5.1801 × |
51801 in other forms
| Form | Value |
|---|---|
| In words | fifty-one thousand eight hundred and one |
| Binary (base 2) | 1100101001011001 |
| Octal (base 8) | 145131 |
| Hexadecimal (base 16) | CA59 |
| Base 3 | 2122001120 |
| As time | 51801 seconds = 14 h 23 min 21 s |
Is 51801 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (51801 ÷ 3 = 17267) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 1) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 1) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 3) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 1) | 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 1) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 2) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 51801 a prime number?
No. 51801 = 3 × 31 × 557, so it is divisible by 3.
What are the factors of 51801?
1, 3, 31, 93, 557, 1671, 17267, 51801.
What is 51801 in binary?
1100101001011001 (hexadecimal CA59, octal 145131).
What is the square root of 51801?
About 227.5983.
Is 51801 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 51801?
51801 is a happy number: repeatedly adding the squares of its digits reaches 1.