To find all the divisors of the number 21,252:
- 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 21,252:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
21,252 = 22 × 3 × 7 × 11 × 23
21,252 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 = (2 + 1) × (1 + 1) × (1 + 1) × (1 + 1) × (1 + 1) = 3 × 2 × 2 × 2 × 2 = 48
But to actually calculate the factors, see below...
2. Multiply the prime factors of the number 21,252
- 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
prime factor =
3
composite factor = 2
2 =
4
composite factor = 2 × 3 =
6
prime factor =
7
prime factor =
11
composite factor = 2
2 × 3 =
12
composite factor = 2 × 7 =
14
composite factor = 3 × 7 =
21
composite factor = 2 × 11 =
22
prime factor =
23
composite factor = 2
2 × 7 =
28
composite factor = 3 × 11 =
33
composite factor = 2 × 3 × 7 =
42
composite factor = 2
2 × 11 =
44
composite factor = 2 × 23 =
46
composite factor = 2 × 3 × 11 =
66
composite factor = 3 × 23 =
69
composite factor = 7 × 11 =
77
composite factor = 2
2 × 3 × 7 =
84
composite factor = 2
2 × 23 =
92
composite factor = 2
2 × 3 × 11 =
132
composite factor = 2 × 3 × 23 =
138
This list continues below...
... This list continues from above
composite factor = 2 × 7 × 11 =
154
composite factor = 7 × 23 =
161
composite factor = 3 × 7 × 11 =
231
composite factor = 11 × 23 =
253
composite factor = 2
2 × 3 × 23 =
276
composite factor = 2
2 × 7 × 11 =
308
composite factor = 2 × 7 × 23 =
322
composite factor = 2 × 3 × 7 × 11 =
462
composite factor = 3 × 7 × 23 =
483
composite factor = 2 × 11 × 23 =
506
composite factor = 2
2 × 7 × 23 =
644
composite factor = 3 × 11 × 23 =
759
composite factor = 2
2 × 3 × 7 × 11 =
924
composite factor = 2 × 3 × 7 × 23 =
966
composite factor = 2
2 × 11 × 23 =
1,012
composite factor = 2 × 3 × 11 × 23 =
1,518
composite factor = 7 × 11 × 23 =
1,771
composite factor = 2
2 × 3 × 7 × 23 =
1,932
composite factor = 2
2 × 3 × 11 × 23 =
3,036
composite factor = 2 × 7 × 11 × 23 =
3,542
composite factor = 3 × 7 × 11 × 23 =
5,313
composite factor = 2
2 × 7 × 11 × 23 =
7,084
composite factor = 2 × 3 × 7 × 11 × 23 =
10,626
composite factor = 2
2 × 3 × 7 × 11 × 23 =
21,252
48 factors (divisors)
What times what is 21,252?
What number multiplied by what number equals 21,252?
All the combinations of any two natural numbers whose product equals 21,252.
1 × 21,252 = 21,252
2 × 10,626 = 21,252
3 × 7,084 = 21,252
4 × 5,313 = 21,252
6 × 3,542 = 21,252
7 × 3,036 = 21,252
11 × 1,932 = 21,252
12 × 1,771 = 21,252
14 × 1,518 = 21,252
21 × 1,012 = 21,252
22 × 966 = 21,252
23 × 924 = 21,252
28 × 759 = 21,252
33 × 644 = 21,252
42 × 506 = 21,252
44 × 483 = 21,252
46 × 462 = 21,252
66 × 322 = 21,252
69 × 308 = 21,252
77 × 276 = 21,252
84 × 253 = 21,252
92 × 231 = 21,252
132 × 161 = 21,252
138 × 154 = 21,252
24 unique multiplications The final answer:
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