The number 91378
91378 is a triangular number: 1 + 2 + … + 427 = 91378. Its prime factorisation is 2 × 7 × 61 × 107. Divisors (16): 1, 2, 7, 14, 61, 107, 122, 214, 427, 749, 854, 1498, 6527, 13054, 45689, 91378.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 91378: a triangular number: 1 + 2 + … + 427 = 91378.
- 2
91378 is composite. Its prime factorisation is
- 3
The divisors add up to 160704; without 91378 itself that is 69326, so 91378 is deficient (69326 is less than 91378). Euler's totient φ(91378) = 38160 numbers up to 91378 share no factor with it.
- 4
The digits of 91378 add up to 28, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 133 steps to reach 1.
LaTeX source of the formulas on this page
\[ 91378 = 2 \times 7 \times 61 \times 107 \]
91378 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 160704 |
| Euler totient φ(n) | 38160 |
| Square | 8349938884 |
| Cube | 763000715342152 |
| Square root | 302.287942 |
| Digit sum / digital root | 28 / 1 |
| Collatz steps to 1 | 133 |
| Scientific notation | 9.1378 × |
91378 in other forms
| Form | Value |
|---|---|
| In words | ninety-one thousand three hundred and seventy-eight |
| Binary (base 2) | 10110010011110010 |
| Octal (base 8) | 262362 |
| Hexadecimal (base 16) | 164F2 |
| Base 3 | 11122100101 |
| As time | 91378 seconds = 25 h 22 min 58 s |
Is 91378 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (91378 ÷ 2 = 45689) | 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 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 3) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (91378 ÷ 7 = 13054) | 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 2) | 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 8) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 1) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 10) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 91378 a prime number?
No. 91378 = 2 × 7 × 61 × 107, so it is divisible by 2.
What are the factors of 91378?
1, 2, 7, 14, 61, 107, 122, 214, 427, 749, 854, 1498, 6527, 13054, 45689, 91378.
What is 91378 in binary?
10110010011110010 (hexadecimal 164F2, octal 262362).
What is the square root of 91378?
About 302.2879.
Is 91378 divisible by 3?
No. Its digits add up to 28, which is not a multiple of 3.
What is special about the number 91378?
91378 is a triangular number: 1 + 2 + … + 427 = 91378.