Identifying Prime Factors: The Sure Inclusion in Two-Digit Numbers

Question

I am a two-digit number $?0$

Which prime factor will surely appear among my first factors?

00:00 Which factor definitely appears in the prime factors of the number?

00:04 The ones digit is 0, therefore the number is even

00:07 Every even number is divisible by 2

00:13 Actually, any number with tens digit and ones digit being 0 is divisible by 5

00:20 And this is the solution to the question

$2$