The number 551
551 is a composite number with 4 divisors. Its prime factorisation is 19 × 29. Divisors (4): 1, 19, 29, 551.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 551: a semiprime: 19 × 29, the product of two primes.
- 2
551 is composite. Its prime factorisation is
- 3
The divisors add up to 600; without 551 itself that is 49, so 551 is deficient (49 is less than 551). Euler's totient φ(551) = 504 numbers up to 551 share no factor with it.
- 4
The digits of 551 add up to 11, and repeating that until one digit is left gives the digital root 2. The Collatz sequence (halve if even, else 3n+1) takes 43 steps to reach 1.
LaTeX source of the formulas on this page
\[ 551 = 19 \times 29 \]
551 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 600 |
| Euler totient φ(n) | 504 |
| Square | 303601 |
| Cube | 167284151 |
| Square root | 23.473389 |
| Digit sum / digital root | 11 / 2 |
| Collatz steps to 1 | 43 |
| Scientific notation | 5.51 × |
551 in other forms
| Form | Value |
|---|---|
| In words | five hundred and fifty-one |
| Roman numerals | DLI |
| Binary (base 2) | 1000100111 |
| Octal (base 8) | 1047 |
| Hexadecimal (base 16) | 227 |
| Base 3 | 202102 |
| As time | 551 seconds = 9 min 11 s |
Is 551 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 1) | 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 7) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 2) | 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 | No (remainder 1) | 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 551 a prime number?
No. 551 = 19 × 29, so it is divisible by 19.
What are the factors of 551?
1, 19, 29, 551.
What is 551 in binary?
1000100111 (hexadecimal 227, octal 1047).
What is the square root of 551?
About 23.4734.
What is 551 in Roman numerals?
DLI.
Is 551 divisible by 3?
No. Its digits add up to 11, which is not a multiple of 3.
What is special about the number 551?
551 is a semiprime: 19 × 29, the product of two primes.