The number 2987
2987 is a composite number with 4 divisors. Its prime factorisation is 29 × 103. Divisors (4): 1, 29, 103, 2987.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 2987: a semiprime: 29 × 103, the product of two primes.
- 2
2987 is composite. Its prime factorisation is
- 3
The divisors add up to 3120; without 2987 itself that is 133, so 2987 is deficient (133 is less than 2987). Euler's totient φ(2987) = 2856 numbers up to 2987 share no factor with it.
- 4
The digits of 2987 add up to 26, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 48 steps to reach 1.
LaTeX source of the formulas on this page
\[ 2987 = 29 \times 103 \]
2987 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 3120 |
| Euler totient φ(n) | 2856 |
| Square | 8922169 |
| Cube | 26650518803 |
| Square root | 54.653454 |
| Digit sum / digital root | 26 / 8 |
| Collatz steps to 1 | 48 |
| Scientific notation | 2.987 × |
2987 in other forms
| Form | Value |
|---|---|
| In words | two thousand nine hundred and eighty-seven |
| Roman numerals | MMCMLXXXVII |
| Binary (base 2) | 101110101011 |
| Octal (base 8) | 5653 |
| Hexadecimal (base 16) | BAB |
| Base 3 | 11002122 |
| As time | 2987 seconds = 49 min 47 s |
Is 2987 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 2) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 3) | 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 5) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 5) | 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 3) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 8) | 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 6) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 11) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 2987 a prime number?
No. 2987 = 29 × 103, so it is divisible by 29.
What are the factors of 2987?
1, 29, 103, 2987.
What is 2987 in binary?
101110101011 (hexadecimal BAB, octal 5653).
What is the square root of 2987?
About 54.6535.
What is 2987 in Roman numerals?
MMCMLXXXVII.
Is 2987 divisible by 3?
No. Its digits add up to 26, which is not a multiple of 3.
What is special about the number 2987?
2987 is a semiprime: 29 × 103, the product of two primes.