1 and 1 divide ( are divisors of ) every integer , every integer is a divisor of itself , and every integer is a divisor of 0 , except by convention 0 itself ( see also division by zero ) . 1 and 1 divide ( are divisors of ) every integer , every integer ( and its negation ) is a divisor of itself , and every integer is a divisor of 0 , except by convention 0 itself ( see also division by zero ) .