To find all the divisors of the number 213,440:
- 1. Decompose the number into prime factors.
- See how you can find out how many factors (divisors) the number has, without actually calculating them.
- 2. Multiply the prime factors in all their unique combinations, that yield different results.
1. Carry out the prime factorization of the number 213,440:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
213,440 = 26 × 5 × 23 × 29
213,440 is not a prime number but a composite one.
- Prime number: a natural number that is divisible (divided evenly) only by 1 and itself. A prime number has exactly two factors: 1 and the number itself.
- Examples of prime numbers: 2 (factors 1, 2), 3 (factors 1, 3), 5 (factors 1, 5), 7 (factors 1, 7), 11 (factors 1, 11), 13 (factors 1, 13), ...
- Composite number: a natural number that has at least one factor other than 1 and itself. So it is neither a prime number nor 1.
- Examples of composite numbers: 4 (it has 3 factors: 1, 2, 4), 6 (it has 4 factors: 1, 2, 3, 6), 8 (it has 4 factors: 1, 2, 4, 8), 9 (it has 3 factors: 1, 3, 9), 10 (it has 4 factors: 1, 2, 5, 10), 12 (it has 6 factors: 1, 2, 3, 4, 6, 12), ...
How to count the number of factors of a number?
Without actually finding the factors
- If a number N is prime factorized as:
N = am × bk × cz
where a, b, c are the prime factors and m, k, z are their exponents, natural numbers, .... - ...
- Then the number of factors of the number N can be calculated as:
n = (m + 1) × (k + 1) × (z + 1) - ...
- In our case, the number of factors is calculated as:
- n = (6 + 1) × (1 + 1) × (1 + 1) × (1 + 1) = 7 × 2 × 2 × 2 = 56
But to actually calculate the factors, see below...
2. Multiply the prime factors of the number 213,440
- Multiply the prime factors involved in the prime factorization of the number in all their unique combinations, that give different results.
- Also consider the exponents of these prime factors.
- Also add 1 to the list of factors (divisors). All the numbers are divisible by 1.
All the factors (divisors) are listed below - in ascending order
The list of factors (divisors):
Numbers other than 1 that are not prime factors are composite factors (divisors).
neither prime nor composite =
1
prime factor =
2
composite factor = 2
2 =
4
prime factor =
5
composite factor = 2
3 =
8
composite factor = 2 × 5 =
10
composite factor = 2
4 =
16
composite factor = 2
2 × 5 =
20
prime factor =
23
prime factor =
29
composite factor = 2
5 =
32
composite factor = 2
3 × 5 =
40
composite factor = 2 × 23 =
46
composite factor = 2 × 29 =
58
composite factor = 2
6 =
64
composite factor = 2
4 × 5 =
80
composite factor = 2
2 × 23 =
92
composite factor = 5 × 23 =
115
composite factor = 2
2 × 29 =
116
composite factor = 5 × 29 =
145
composite factor = 2
5 × 5 =
160
composite factor = 2
3 × 23 =
184
composite factor = 2 × 5 × 23 =
230
composite factor = 2
3 × 29 =
232
composite factor = 2 × 5 × 29 =
290
composite factor = 2
6 × 5 =
320
composite factor = 2
4 × 23 =
368
composite factor = 2
2 × 5 × 23 =
460
This list continues below...
... This list continues from above
composite factor = 2
4 × 29 =
464
composite factor = 2
2 × 5 × 29 =
580
composite factor = 23 × 29 =
667
composite factor = 2
5 × 23 =
736
composite factor = 2
3 × 5 × 23 =
920
composite factor = 2
5 × 29 =
928
composite factor = 2
3 × 5 × 29 =
1,160
composite factor = 2 × 23 × 29 =
1,334
composite factor = 2
6 × 23 =
1,472
composite factor = 2
4 × 5 × 23 =
1,840
composite factor = 2
6 × 29 =
1,856
composite factor = 2
4 × 5 × 29 =
2,320
composite factor = 2
2 × 23 × 29 =
2,668
composite factor = 5 × 23 × 29 =
3,335
composite factor = 2
5 × 5 × 23 =
3,680
composite factor = 2
5 × 5 × 29 =
4,640
composite factor = 2
3 × 23 × 29 =
5,336
composite factor = 2 × 5 × 23 × 29 =
6,670
composite factor = 2
6 × 5 × 23 =
7,360
composite factor = 2
6 × 5 × 29 =
9,280
composite factor = 2
4 × 23 × 29 =
10,672
composite factor = 2
2 × 5 × 23 × 29 =
13,340
composite factor = 2
5 × 23 × 29 =
21,344
composite factor = 2
3 × 5 × 23 × 29 =
26,680
composite factor = 2
6 × 23 × 29 =
42,688
composite factor = 2
4 × 5 × 23 × 29 =
53,360
composite factor = 2
5 × 5 × 23 × 29 =
106,720
composite factor = 2
6 × 5 × 23 × 29 =
213,440
56 factors (divisors)
What times what is 213,440?
What number multiplied by what number equals 213,440?
All the combinations of any two natural numbers whose product equals 213,440.
1 × 213,440 = 213,440
2 × 106,720 = 213,440
4 × 53,360 = 213,440
5 × 42,688 = 213,440
8 × 26,680 = 213,440
10 × 21,344 = 213,440
16 × 13,340 = 213,440
20 × 10,672 = 213,440
23 × 9,280 = 213,440
29 × 7,360 = 213,440
32 × 6,670 = 213,440
40 × 5,336 = 213,440
46 × 4,640 = 213,440
58 × 3,680 = 213,440
64 × 3,335 = 213,440
80 × 2,668 = 213,440
92 × 2,320 = 213,440
115 × 1,856 = 213,440
116 × 1,840 = 213,440
145 × 1,472 = 213,440
160 × 1,334 = 213,440
184 × 1,160 = 213,440
230 × 928 = 213,440
232 × 920 = 213,440
290 × 736 = 213,440
320 × 667 = 213,440
368 × 580 = 213,440
460 × 464 = 213,440
28 unique multiplications The final answer:
(scroll down)