To find all the divisors of the number 85,642,720:
- 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 85,642,720:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
85,642,720 = 25 × 5 × 83 × 6,449
85,642,720 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 = (5 + 1) × (1 + 1) × (1 + 1) × (1 + 1) = 6 × 2 × 2 × 2 = 48
But to actually calculate the factors, see below...
2. Multiply the prime factors of the number 85,642,720
- 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
composite factor = 2
5 =
32
composite factor = 2
3 × 5 =
40
composite factor = 2
4 × 5 =
80
prime factor =
83
composite factor = 2
5 × 5 =
160
composite factor = 2 × 83 =
166
composite factor = 2
2 × 83 =
332
composite factor = 5 × 83 =
415
composite factor = 2
3 × 83 =
664
composite factor = 2 × 5 × 83 =
830
composite factor = 2
4 × 83 =
1,328
composite factor = 2
2 × 5 × 83 =
1,660
composite factor = 2
5 × 83 =
2,656
composite factor = 2
3 × 5 × 83 =
3,320
prime factor =
6,449
composite factor = 2
4 × 5 × 83 =
6,640
This list continues below...
... This list continues from above
composite factor = 2 × 6,449 =
12,898
composite factor = 2
5 × 5 × 83 =
13,280
composite factor = 2
2 × 6,449 =
25,796
composite factor = 5 × 6,449 =
32,245
composite factor = 2
3 × 6,449 =
51,592
composite factor = 2 × 5 × 6,449 =
64,490
composite factor = 2
4 × 6,449 =
103,184
composite factor = 2
2 × 5 × 6,449 =
128,980
composite factor = 2
5 × 6,449 =
206,368
composite factor = 2
3 × 5 × 6,449 =
257,960
composite factor = 2
4 × 5 × 6,449 =
515,920
composite factor = 83 × 6,449 =
535,267
composite factor = 2
5 × 5 × 6,449 =
1,031,840
composite factor = 2 × 83 × 6,449 =
1,070,534
composite factor = 2
2 × 83 × 6,449 =
2,141,068
composite factor = 5 × 83 × 6,449 =
2,676,335
composite factor = 2
3 × 83 × 6,449 =
4,282,136
composite factor = 2 × 5 × 83 × 6,449 =
5,352,670
composite factor = 2
4 × 83 × 6,449 =
8,564,272
composite factor = 2
2 × 5 × 83 × 6,449 =
10,705,340
composite factor = 2
5 × 83 × 6,449 =
17,128,544
composite factor = 2
3 × 5 × 83 × 6,449 =
21,410,680
composite factor = 2
4 × 5 × 83 × 6,449 =
42,821,360
composite factor = 2
5 × 5 × 83 × 6,449 =
85,642,720
48 factors (divisors)
What times what is 85,642,720?
What number multiplied by what number equals 85,642,720?
All the combinations of any two natural numbers whose product equals 85,642,720.
1 × 85,642,720 = 85,642,720
2 × 42,821,360 = 85,642,720
4 × 21,410,680 = 85,642,720
5 × 17,128,544 = 85,642,720
8 × 10,705,340 = 85,642,720
10 × 8,564,272 = 85,642,720
16 × 5,352,670 = 85,642,720
20 × 4,282,136 = 85,642,720
32 × 2,676,335 = 85,642,720
40 × 2,141,068 = 85,642,720
80 × 1,070,534 = 85,642,720
83 × 1,031,840 = 85,642,720
160 × 535,267 = 85,642,720
166 × 515,920 = 85,642,720
332 × 257,960 = 85,642,720
415 × 206,368 = 85,642,720
664 × 128,980 = 85,642,720
830 × 103,184 = 85,642,720
1,328 × 64,490 = 85,642,720
1,660 × 51,592 = 85,642,720
2,656 × 32,245 = 85,642,720
3,320 × 25,796 = 85,642,720
6,449 × 13,280 = 85,642,720
6,640 × 12,898 = 85,642,720
24 unique multiplications The final answer:
(scroll down)