The number 78001
78001 is a composite number with 8 divisors. Its prime factorisation is 7 × 11 × 1013. Divisors (8): 1, 7, 11, 77, 1013, 7091, 11143, 78001.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
78001 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
78001 is composite. Its prime factorisation is
- 3
The divisors add up to 97344; without 78001 itself that is 19343, so 78001 is deficient (19343 is less than 78001). Euler's totient φ(78001) = 60720 numbers up to 78001 share no factor with it.
- 4
The digits of 78001 add up to 16, and repeating that until one digit is left gives the digital root 7. The Collatz sequence (halve if even, else 3n+1) takes 50 steps to reach 1.
LaTeX source of the formulas on this page
\[ 78001 = 7 \times 11 \times 1013 \]
78001 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 97344 |
| Euler totient φ(n) | 60720 |
| Square | 6084156001 |
| Cube | 474570252234001 |
| Square root | 279.286591 |
| Digit sum / digital root | 16 / 7 |
| Collatz steps to 1 | 50 |
| Scientific notation | 7.8001 × |
78001 in other forms
| Form | Value |
|---|---|
| In words | seventy-eight thousand and one |
| Binary (base 2) | 10011000010110001 |
| Octal (base 8) | 230261 |
| Hexadecimal (base 16) | 130B1 |
| Base 3 | 10221222221 |
| As time | 78001 seconds = 21 h 40 min 1 s |
Is 78001 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 | Yes (78001 ÷ 7 = 11143) | 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 7) | 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 | Yes (78001 ÷ 11 = 7091) | 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 78001 a prime number?
No. 78001 = 7 × 11 × 1013, so it is divisible by 7.
What are the factors of 78001?
1, 7, 11, 77, 1013, 7091, 11143, 78001.
What is 78001 in binary?
10011000010110001 (hexadecimal 130B1, octal 230261).
What is the square root of 78001?
About 279.2866.
Is 78001 divisible by 3?
No. Its digits add up to 16, which is not a multiple of 3.
What is special about the number 78001?
It is a composite number with 8 divisors.