Deficient Number Calculator

Input a number to determine if it is deficient; or define a range to generate all deficient numbers within it.

Deficient Number Check or Generate

What Is a Deficient Number?

A deficient number is the opposite of an abundant number. It is a positive integer whose proper divisors (excluding itself) sum to a value less than the number itself. For example: 8 is a deficient number because its divisors (1, 2, 4) sum to 7, which is less than 8.

How to Determine if a Number Is Deficient

  1. Find Divisors: Identify all proper divisors of the number (excluding the number itself). For example, the divisors of 25 are 1 and 5.
  2. Calculate the Sum of Divisors: Add up all the divisors. For 25, 1 + 5 = 6 .
  3. Check the Result: If the sum of the divisors is less than the number, it is a deficient number. Otherwise, it is not.

Examples

Example 1: Is 15 a deficient number?

Solution:

1. Find divisors:

The proper divisors of 15 are 1, 3, and 5.

2. Sum of divisors:

1 + 3 + 5 = 9

3. Check the Result:

9 < 15

Conclusion: Since 9 < 15, 15 is a deficient number.

Example 2: Is 28 a deficient number?

Solution:

1. Find divisors:

The proper divisors of 28 are 1, 2, 4, 7, and 14.

2. Sum of divisors:

1 + 2 + 4 + 7 + 14 = 28

Conclusion: 28 is a perfect number, not a deficient number.

Example 3: Is 96 a deficient number?

Solution:

1. Find divisors:

The proper divisors of 96 are 1, 2, 3, 4, 6, 8, 12, 16, 24, 32, and 48.

2. Sum of divisors:

1 + 2 + 3 + 4 + 6 + 8 + 12 + 16 + 24 + 32 + 48 = 156

3. Check the Result:

156 > 96

Conclusion: Since 156 > 96, 96 is not a deficient number, it is an abundant number.

The First 100 Deficient Numbers

  • 1
  • 2
  • 3
  • 4
  • 5
  • 7
  • 8
  • 9
  • 10
  • 11
  • 13
  • 14
  • 15
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  • 25
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  • 29
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  • 49
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