The number 7977
7977 is a composite number with 4 divisors. Its prime factorisation is 3 × 2659. Divisors (4): 1, 3, 2659, 7977.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 7977: a semiprime: 3 × 2659, the product of two primes.
- 2
7977 is composite. Its prime factorisation is
- 3
The divisors add up to 10640; without 7977 itself that is 2663, so 7977 is deficient (2663 is less than 7977). Euler's totient φ(7977) = 5316 numbers up to 7977 share no factor with it.
- 4
The digits of 7977 add up to 30, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 52 steps to reach 1.
LaTeX source of the formulas on this page
\[ 7977 = 3 \times 2659 \]
7977 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 10640 |
| Euler totient φ(n) | 5316 |
| Square | 63632529 |
| Cube | 507596683833 |
| Square root | 89.314053 |
| Digit sum / digital root | 30 / 3 |
| Collatz steps to 1 | 52 |
| Scientific notation | 7.977 × |
7977 in other forms
| Form | Value |
|---|---|
| In words | seven thousand nine hundred and seventy-seven |
| Binary (base 2) | 1111100101001 |
| Octal (base 8) | 17451 |
| Hexadecimal (base 16) | 1F29 |
| Base 3 | 101221110 |
| As time | 7977 seconds = 2 h 12 min 57 s |
Is 7977 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 (7977 ÷ 3 = 2659) | 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 2) | 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 4) | 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 3) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 7) | 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 7977 a prime number?
No. 7977 = 3 × 2659, so it is divisible by 3.
What are the factors of 7977?
1, 3, 2659, 7977.
What is 7977 in binary?
1111100101001 (hexadecimal 1F29, octal 17451).
What is the square root of 7977?
About 89.3141.
Is 7977 divisible by 3?
Yes. Its digits add up to 30, a multiple of 3.
What is special about the number 7977?
7977 is a semiprime: 3 × 2659, the product of two primes.