Question

For which of the following numbers, all its digits are its factors?

• A. 135
• B. 19
• C. 25
• D. 35

Answer 1

The correct option is A 135

$135=3\times 45$
$=9\times 15$
$=27\times 5$
$=1\times 135$
Factors of 135 = 1, 3, 5, 9, 15, 27, 45, 135. Hence, 135 has all its digits as factors.

$19=1\times 19$
Therefore, factors of 19 = 1 and 19.


$25=5\times 5$
$=1\times 25$
Therefore, factors of 25 = 1, 5 and 25.

$35=5\times 7$
$=1\times 35$
Therefore, factors of 35 = 1, 5, 7 and 35.