The number 1553
1553 is the 245th prime number. Its only divisors are 1 and 1553.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 1553: the 245th prime number.
- 2
1553 is prime, so its only factors are 1 and 1553. It is the 245th prime; the next prime is 1559 and the one before is 1549.
- 3
The divisors add up to 1554; without 1553 itself that is 1, so 1553 is deficient (1 is less than 1553). Euler's totient φ(1553) = 1552 numbers up to 1553 share no factor with it.
- 4
The digits of 1553 add up to 14, and repeating that until one digit is left gives the digital root 5. The Collatz sequence (halve if even, else 3n+1) takes 122 steps to reach 1.
1553 at a glance
| Property | Value |
|---|---|
| Type | prime |
| Number of divisors | 2 |
| Sum of divisors | 1554 |
| Euler totient φ(n) | 1552 |
| Square | 2411809 |
| Cube | 3745539377 |
| Square root | 39.408121 |
| Digit sum / digital root | 14 / 5 |
| Collatz steps to 1 | 122 |
| Scientific notation | 1.553 × |
1553 in other forms
| Form | Value |
|---|---|
| In words | one thousand five hundred and fifty-three |
| Roman numerals | MDLIII |
| Binary (base 2) | 11000010001 |
| Octal (base 8) | 3021 |
| Hexadecimal (base 16) | 611 |
| Base 3 | 2010112 |
| As time | 1553 seconds = 25 min 53 s |
Is 1553 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 3) | 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 1) | 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 3) | 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 1553 a prime number?
Yes. 1553 is divisible only by 1 and itself.
What are the factors of 1553?
1, 1553.
What is 1553 in binary?
11000010001 (hexadecimal 611, octal 3021).
What is the square root of 1553?
About 39.4081.
What is 1553 in Roman numerals?
MDLIII.
Is 1553 divisible by 3?
No. Its digits add up to 14, which is not a multiple of 3.
What is special about the number 1553?
1553 is the 245th prime number.