The number 1977
1977 is a composite number with 4 divisors. Its prime factorisation is 3 × 659. Divisors (4): 1, 3, 659, 1977.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 1977: a semiprime: 3 × 659, the product of two primes.
- 2
1977 is composite. Its prime factorisation is
- 3
The divisors add up to 2640; without 1977 itself that is 663, so 1977 is deficient (663 is less than 1977). Euler's totient φ(1977) = 1316 numbers up to 1977 share no factor with it.
- 4
The digits of 1977 add up to 24, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 143 steps to reach 1.
LaTeX source of the formulas on this page
\[ 1977 = 3 \times 659 \]
1977 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 2640 |
| Euler totient φ(n) | 1316 |
| Square | 3908529 |
| Cube | 7727161833 |
| Square root | 44.463468 |
| Digit sum / digital root | 24 / 6 |
| Collatz steps to 1 | 143 |
| Scientific notation | 1.977 × |
1977 in other forms
| Form | Value |
|---|---|
| In words | one thousand nine hundred and seventy-seven |
| Roman numerals | MCMLXXVII |
| Binary (base 2) | 11110111001 |
| Octal (base 8) | 3671 |
| Hexadecimal (base 16) | 7B9 |
| Base 3 | 2201020 |
| As time | 1977 seconds = 32 min 57 s |
Is 1977 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 (1977 ÷ 3 = 659) | 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 3) | 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 7) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 8) | 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 1977 a prime number?
No. 1977 = 3 × 659, so it is divisible by 3.
What are the factors of 1977?
1, 3, 659, 1977.
What is 1977 in binary?
11110111001 (hexadecimal 7B9, octal 3671).
What is the square root of 1977?
About 44.4635.
What is 1977 in Roman numerals?
MCMLXXVII.
Is 1977 divisible by 3?
Yes. Its digits add up to 24, a multiple of 3.
What is special about the number 1977?
1977 is a semiprime: 3 × 659, the product of two primes.