The number 1421
1421 is a binary palindrome (10110001101). Its prime factorisation is Ć 29. Divisors (6): 1, 7, 29, 49, 203, 1421.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 1421: a binary palindrome (10110001101).
- 2
1421 is composite. Its prime factorisation is
- 3
The divisors add up to 1710; without 1421 itself that is 289, so 1421 is deficient (289 is less than 1421). Euler's totient Ļ(1421) = 1176 numbers up to 1421 share no factor with it.
- 4
The digits of 1421 add up to 8, and repeating that until one digit is left gives the digital root 8. The Collatz sequence (halve if even, else 3n+1) takes 34 steps to reach 1.
LaTeX source of the formulas on this page
\[ 1421 = 7^{2} \times 29 \]1421 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 6 |
| Sum of divisors | 1710 |
| Euler totient Ļ(n) | 1176 |
| Square | 2019241 |
| Cube | 2869341461 |
| Square root | 37.696154 (= 7ā29) |
| Digit sum / digital root | 8 / 8 |
| Collatz steps to 1 | 34 |
| Scientific notation | 1.421 Ć |
1421 in other forms
| Form | Value |
|---|---|
| In words | one thousand four hundred and twenty-one |
| Roman numerals | MCDXXI |
| Binary (base 2) | 10110001101 |
| Octal (base 8) | 2615 |
| Hexadecimal (base 16) | 58D |
| Base 3 | 1221122 |
| As time | 1421 seconds = 23 min 41 s |
Is 1421 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 1) | 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 | Yes (1421 Ć· 7 = 203) | 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 5) | 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 1) | 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 5) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 1421 a prime number?
No. 1421 = Ć 29, so it is divisible by 7.
What are the factors of 1421?
1, 7, 29, 49, 203, 1421.
What is 1421 in binary?
10110001101 (hexadecimal 58D, octal 2615).
What is the square root of 1421?
About 37.6962, exactly 7ā29.
What is 1421 in Roman numerals?
MCDXXI.
Is 1421 divisible by 3?
No. Its digits add up to 8, which is not a multiple of 3.
What is special about the number 1421?
1421 is a binary palindrome (10110001101).