The number 29890
29890 is a triangular number: 1 + 2 + … + 244 = 29890. Its prime factorisation is 2 × 5 × × 61. Divisors (24): 1, 2, 5, 7, 10, 14, 35, 49, 61, 70, 98, 122, 245, 305, 427, 490 … 29890.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 29890: a triangular number: 1 + 2 + … + 244 = 29890; a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
29890 is composite. Its prime factorisation is
- 3
The divisors add up to 63612; without 29890 itself that is 33722, so 29890 is abundant (33722 is more than 29890). Euler's totient φ(29890) = 10080 numbers up to 29890 share no factor with it.
- 4
The digits of 29890 add up to 28, and repeating that until one digit is left gives the digital root 1. The Collatz sequence (halve if even, else 3n+1) takes 72 steps to reach 1.
LaTeX source of the formulas on this page
\[ 29890 = 2 \times 5 \times 7^{2} \times 61 \]29890 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 24 |
| Sum of divisors | 63612 |
| Euler totient φ(n) | 10080 |
| Square | 893412100 |
| Cube | 26704087669000 |
| Square root | 172.887246 (= 7√610) |
| Digit sum / digital root | 28 / 1 |
| Collatz steps to 1 | 72 |
| Scientific notation | 2.989 × |
29890 in other forms
| Form | Value |
|---|---|
| In words | twenty-nine thousand eight hundred and ninety |
| Binary (base 2) | 111010011000010 |
| Octal (base 8) | 72302 |
| Hexadecimal (base 16) | 74C2 |
| Base 3 | 1112000001 |
| As time | 29890 seconds = 8 h 18 min 10 s |
Is 29890 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (29890 ÷ 2 = 14945) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | No (remainder 1) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | Yes (29890 ÷ 5 = 5978) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 4) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (29890 ÷ 7 = 4270) | 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 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 1) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | Yes (29890 ÷ 10 = 2989) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 3) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 10) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 29890 a prime number?
No. 29890 = 2 × 5 × × 61, so it is divisible by 2.
What are the factors of 29890?
1, 2, 5, 7, 10, 14, 35, 49, 61, 70, 98, 122, 245, 305, 427, 490, 610, 854, 2135, 2989, 4270, 5978, 14945, 29890.
What is 29890 in binary?
111010011000010 (hexadecimal 74C2, octal 72302).
What is the square root of 29890?
About 172.8872, exactly 7√610.
Is 29890 divisible by 3?
No. Its digits add up to 28, which is not a multiple of 3.
What is special about the number 29890?
29890 is a triangular number: 1 + 2 + … + 244 = 29890; a happy number: repeatedly adding the squares of its digits reaches 1.