An even number can be split into two equal whole groups. 4, 10, and 256 are even. The last digit is 0, 2, 4, 6, or 8. Zero is even because 0 ÷ 2 = 0 with no remainder.

Even numbers have simple properties. The sum of two evens is even. The product of an even and any integer is even. These rules help in mental arithmetic and in proofs. Parity—whether a number is even or odd—is a basic concept in number theory.

Even numbers appear in symmetry, pairing, and divisibility tests. In computer science, the least significant bit determines parity, which is useful in algorithms and error checking. The concept is elementary, but it connects to deep ideas in algebra and number theory.

• Integer divisible by two
• Last digit is 0, 2, 4, 6, or 8
• Zero is even
• Parity is fundamental in number theory