In mathematics, the greatest common divisor (GCD) of two or more integers, when at least one of them is not zero, is the largest positive integer that divides the numbers without a remainder.
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For example, the GCD of 20 and 25 is 5.
- Greatest common factor (GCF),
- Highest common factor (HCF),
- Greatest common measure (GCM),
- Highest common divisor (HCD)