We say an integer b evenly divides another integer c if c/b is a whole number. Actually, nobody in mathematics ever says that b ``evenly divides'' c -people just say b ``divides'' c. Another way to say the same thing is to say that b is a divisor of c. The divisors of c are the numbers that (evenly) divide c. Finally, one can also say that b is divisible by c.
Examples:
3 divides 12.
3 is a divisor of 9.
40 is not a divisor of 20.
40 is divisible by 20.
4 divides 4.
5 is a divisor of -10.
12 divides 60.
The positive divisors of 50 are 1, 2, 5, 10, 25, and 50.