To find all the divisors of the number 211,420:
- 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 211,420:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
211,420 = 22 × 5 × 11 × 312
211,420 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) × (2 + 1) = 3 × 2 × 2 × 3 = 36
But to actually calculate the factors, see below...
2. Multiply the prime factors of the number 211,420
- 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 × 5 =
10
prime factor =
11
composite factor = 2
2 × 5 =
20
composite factor = 2 × 11 =
22
prime factor =
31
composite factor = 2
2 × 11 =
44
composite factor = 5 × 11 =
55
composite factor = 2 × 31 =
62
composite factor = 2 × 5 × 11 =
110
composite factor = 2
2 × 31 =
124
composite factor = 5 × 31 =
155
composite factor = 2
2 × 5 × 11 =
220
composite factor = 2 × 5 × 31 =
310
composite factor = 11 × 31 =
341
This list continues below...
... This list continues from above
composite factor = 2
2 × 5 × 31 =
620
composite factor = 2 × 11 × 31 =
682
composite factor = 31
2 =
961
composite factor = 2
2 × 11 × 31 =
1,364
composite factor = 5 × 11 × 31 =
1,705
composite factor = 2 × 31
2 =
1,922
composite factor = 2 × 5 × 11 × 31 =
3,410
composite factor = 2
2 × 31
2 =
3,844
composite factor = 5 × 31
2 =
4,805
composite factor = 2
2 × 5 × 11 × 31 =
6,820
composite factor = 2 × 5 × 31
2 =
9,610
composite factor = 11 × 31
2 =
10,571
composite factor = 2
2 × 5 × 31
2 =
19,220
composite factor = 2 × 11 × 31
2 =
21,142
composite factor = 2
2 × 11 × 31
2 =
42,284
composite factor = 5 × 11 × 31
2 =
52,855
composite factor = 2 × 5 × 11 × 31
2 =
105,710
composite factor = 2
2 × 5 × 11 × 31
2 =
211,420
36 factors (divisors)
What times what is 211,420?
What number multiplied by what number equals 211,420?
All the combinations of any two natural numbers whose product equals 211,420.
1 × 211,420 = 211,420
2 × 105,710 = 211,420
4 × 52,855 = 211,420
5 × 42,284 = 211,420
10 × 21,142 = 211,420
11 × 19,220 = 211,420
20 × 10,571 = 211,420
22 × 9,610 = 211,420
31 × 6,820 = 211,420
44 × 4,805 = 211,420
55 × 3,844 = 211,420
62 × 3,410 = 211,420
110 × 1,922 = 211,420
124 × 1,705 = 211,420
155 × 1,364 = 211,420
220 × 961 = 211,420
310 × 682 = 211,420
341 × 620 = 211,420
18 unique multiplications The final answer:
(scroll down)