The number 1679
1679 is a composite number with 4 divisors. Its prime factorisation is 23 × 73. Divisors (4): 1, 23, 73, 1679.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 1679: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 23; a semiprime: 23 × 73, the product of two primes.
- 2
1679 is composite. Its prime factorisation is
- 3
The divisors add up to 1776; without 1679 itself that is 97, so 1679 is deficient (97 is less than 1679). Euler's totient φ(1679) = 1584 numbers up to 1679 share no factor with it.
- 4
The digits of 1679 add up to 23, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 86 steps to reach 1.
LaTeX source of the formulas on this page
\[ 1679 = 23 \times 73 \]
1679 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 4 |
| Sum of divisors | 1776 |
| Euler totient φ(n) | 1584 |
| Square | 2819041 |
| Cube | 4733169839 |
| Square root | 40.975602 |
| Digit sum / digital root | 23 / 5 |
| Collatz steps to 1 | 86 |
| Scientific notation | 1.679 × |
1679 in other forms
| Form | Value |
|---|---|
| In words | one thousand six hundred and seventy-nine |
| Roman numerals | MDCLXXIX |
| Binary (base 2) | 11010001111 |
| Octal (base 8) | 3217 |
| Hexadecimal (base 16) | 68F |
| Base 3 | 2022012 |
| As time | 1679 seconds = 27 min 59 s |
Is 1679 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 4) | 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 6) | 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 5) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 9) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 7) | 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 1679 a prime number?
No. 1679 = 23 × 73, so it is divisible by 23.
What are the factors of 1679?
1, 23, 73, 1679.
What is 1679 in binary?
11010001111 (hexadecimal 68F, octal 3217).
What is the square root of 1679?
About 40.9756.
What is 1679 in Roman numerals?
MDCLXXIX.
Is 1679 divisible by 3?
No. Its digits add up to 23, which is not a multiple of 3.
What is special about the number 1679?
1679 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 23; a semiprime: 23 × 73, the product of two primes.