The number 18901
18901 is a composite number with 4 divisors. Its prime factorisation is 41 × 461. Divisors (4): 1, 41, 461, 18901.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 18901: a semiprime: 41 × 461, the product of two primes.
- 2
18901 is composite. Its prime factorisation is
- 3
The divisors add up to 19404; without 18901 itself that is 503, so 18901 is deficient (503 is less than 18901). Euler's totient φ(18901) = 18400 numbers up to 18901 share no factor with it.
- 4
The digits of 18901 add up to 19, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 61 steps to reach 1.
LaTeX source of the formulas on this page
\[ 18901 = 41 \times 461 \]
18901 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 19404 |
| Euler totient φ(n) | 18400 |
| Square | 357247801 |
| Cube | 6752340686701 |
| Square root | 137.480908 |
| Digit sum / digital root | 19 / 1 |
| Collatz steps to 1 | 61 |
| Scientific notation | 1.8901 × |
18901 in other forms
| Form | Value |
|---|---|
| In words | eighteen thousand nine hundred and one |
| Binary (base 2) | 100100111010101 |
| Octal (base 8) | 44725 |
| Hexadecimal (base 16) | 49D5 |
| Base 3 | 221221001 |
| As time | 18901 seconds = 5 h 15 min 1 s |
Is 18901 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 | No (remainder 1) | 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 1) | 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 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | 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 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 1) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 18901 a prime number?
No. 18901 = 41 × 461, so it is divisible by 41.
What are the factors of 18901?
1, 41, 461, 18901.
What is 18901 in binary?
100100111010101 (hexadecimal 49D5, octal 44725).
What is the square root of 18901?
About 137.4809.
Is 18901 divisible by 3?
No. Its digits add up to 19, which is not a multiple of 3.
What is special about the number 18901?
18901 is a semiprime: 41 × 461, the product of two primes.