The number 25402
25402 is a composite number with 8 divisors. Its prime factorisation is 2 × 13 × 977. Divisors (8): 1, 2, 13, 26, 977, 1954, 12701, 25402.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 25402: a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 13.
- 2
25402 is composite. Its prime factorisation is
- 3
The divisors add up to 41076; without 25402 itself that is 15674, so 25402 is deficient (15674 is less than 25402). Euler's totient φ(25402) = 11712 numbers up to 25402 share no factor with it.
- 4
The digits of 25402 add up to 13, and repeating that until one digit is left gives the digital root 4. The Collatz sequence (halve if even, else 3n+1) takes 201 steps to reach 1.
LaTeX source of the formulas on this page
\[ 25402 = 2 \times 13 \times 977 \]
25402 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 41076 |
| Euler totient φ(n) | 11712 |
| Square | 645261604 |
| Cube | 16390935264808 |
| Square root | 159.380049 |
| Digit sum / digital root | 13 / 4 |
| Collatz steps to 1 | 201 |
| Scientific notation | 2.5402 × |
25402 in other forms
| Form | Value |
|---|---|
| In words | twenty-five thousand four hundred and two |
| Binary (base 2) | 110001100111010 |
| Octal (base 8) | 61472 |
| Hexadecimal (base 16) | 633A |
| Base 3 | 1021211211 |
| As time | 25402 seconds = 7 h 3 min 22 s |
Is 25402 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (25402 ÷ 2 = 12701) | 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 | No (remainder 2) | 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 | 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 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 4) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 2) | 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 25402 a prime number?
No. 25402 = 2 × 13 × 977, so it is divisible by 2.
What are the factors of 25402?
1, 2, 13, 26, 977, 1954, 12701, 25402.
What is 25402 in binary?
110001100111010 (hexadecimal 633A, octal 61472).
What is the square root of 25402?
About 159.3800.
Is 25402 divisible by 3?
No. Its digits add up to 13, which is not a multiple of 3.
What is special about the number 25402?
25402 is a happy number: repeatedly adding the squares of its digits reaches 1; a Harshad number: divisible by its digit sum 13.