To find all the divisors of the number 13,901,390:
- 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 13,901,390:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
13,901,390 = 2 × 5 × 73 × 137 × 139
13,901,390 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 13,901,390
- 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 =
5
composite factor = 2 × 5 =
10
prime factor =
73
prime factor =
137
prime factor =
139
composite factor = 2 × 73 =
146
composite factor = 2 × 137 =
274
composite factor = 2 × 139 =
278
composite factor = 5 × 73 =
365
composite factor = 5 × 137 =
685
composite factor = 5 × 139 =
695
composite factor = 2 × 5 × 73 =
730
composite factor = 2 × 5 × 137 =
1,370
composite factor = 2 × 5 × 139 =
1,390
This list continues below...
... This list continues from above
composite factor = 73 × 137 =
10,001
composite factor = 73 × 139 =
10,147
composite factor = 137 × 139 =
19,043
composite factor = 2 × 73 × 137 =
20,002
composite factor = 2 × 73 × 139 =
20,294
composite factor = 2 × 137 × 139 =
38,086
composite factor = 5 × 73 × 137 =
50,005
composite factor = 5 × 73 × 139 =
50,735
composite factor = 5 × 137 × 139 =
95,215
composite factor = 2 × 5 × 73 × 137 =
100,010
composite factor = 2 × 5 × 73 × 139 =
101,470
composite factor = 2 × 5 × 137 × 139 =
190,430
composite factor = 73 × 137 × 139 =
1,390,139
composite factor = 2 × 73 × 137 × 139 =
2,780,278
composite factor = 5 × 73 × 137 × 139 =
6,950,695
composite factor = 2 × 5 × 73 × 137 × 139 =
13,901,390
32 factors (divisors)
What times what is 13,901,390?
What number multiplied by what number equals 13,901,390?
All the combinations of any two natural numbers whose product equals 13,901,390.
1 × 13,901,390 = 13,901,390
2 × 6,950,695 = 13,901,390
5 × 2,780,278 = 13,901,390
10 × 1,390,139 = 13,901,390
73 × 190,430 = 13,901,390
137 × 101,470 = 13,901,390
139 × 100,010 = 13,901,390
146 × 95,215 = 13,901,390
274 × 50,735 = 13,901,390
278 × 50,005 = 13,901,390
365 × 38,086 = 13,901,390
685 × 20,294 = 13,901,390
695 × 20,002 = 13,901,390
730 × 19,043 = 13,901,390
1,370 × 10,147 = 13,901,390
1,390 × 10,001 = 13,901,390
16 unique multiplications The final answer:
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