To find all the divisors of the number 20,390,910:
- 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 20,390,910:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
20,390,910 = 2 × 3 × 5 × 103 × 6,599
20,390,910 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 = (1 + 1) × (1 + 1) × (1 + 1) × (1 + 1) × (1 + 1) = 2 × 2 × 2 × 2 × 2 = 32
But to actually calculate the factors, see below...
2. Multiply the prime factors of the number 20,390,910
- Multiply the prime factors involved in the prime factorization of the number in all their unique combinations, that give different results.
- 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
prime factor =
5
composite factor = 2 × 3 =
6
composite factor = 2 × 5 =
10
composite factor = 3 × 5 =
15
composite factor = 2 × 3 × 5 =
30
prime factor =
103
composite factor = 2 × 103 =
206
composite factor = 3 × 103 =
309
composite factor = 5 × 103 =
515
composite factor = 2 × 3 × 103 =
618
composite factor = 2 × 5 × 103 =
1,030
composite factor = 3 × 5 × 103 =
1,545
composite factor = 2 × 3 × 5 × 103 =
3,090
This list continues below...
... This list continues from above
prime factor =
6,599
composite factor = 2 × 6,599 =
13,198
composite factor = 3 × 6,599 =
19,797
composite factor = 5 × 6,599 =
32,995
composite factor = 2 × 3 × 6,599 =
39,594
composite factor = 2 × 5 × 6,599 =
65,990
composite factor = 3 × 5 × 6,599 =
98,985
composite factor = 2 × 3 × 5 × 6,599 =
197,970
composite factor = 103 × 6,599 =
679,697
composite factor = 2 × 103 × 6,599 =
1,359,394
composite factor = 3 × 103 × 6,599 =
2,039,091
composite factor = 5 × 103 × 6,599 =
3,398,485
composite factor = 2 × 3 × 103 × 6,599 =
4,078,182
composite factor = 2 × 5 × 103 × 6,599 =
6,796,970
composite factor = 3 × 5 × 103 × 6,599 =
10,195,455
composite factor = 2 × 3 × 5 × 103 × 6,599 =
20,390,910
32 factors (divisors)
What times what is 20,390,910?
What number multiplied by what number equals 20,390,910?
All the combinations of any two natural numbers whose product equals 20,390,910.
1 × 20,390,910 = 20,390,910
2 × 10,195,455 = 20,390,910
3 × 6,796,970 = 20,390,910
5 × 4,078,182 = 20,390,910
6 × 3,398,485 = 20,390,910
10 × 2,039,091 = 20,390,910
15 × 1,359,394 = 20,390,910
30 × 679,697 = 20,390,910
103 × 197,970 = 20,390,910
206 × 98,985 = 20,390,910
309 × 65,990 = 20,390,910
515 × 39,594 = 20,390,910
618 × 32,995 = 20,390,910
1,030 × 19,797 = 20,390,910
1,545 × 13,198 = 20,390,910
3,090 × 6,599 = 20,390,910
16 unique multiplications The final answer:
(scroll down)