An apostrophe would make it possessive. When you make a word plural you never add an apostrophe .
1. I had two basketballs
2. He has three cars
3. There were 10 girls at the party
If you look at the plural words basketballs, cars, girls, none of them have an apostrophe.
In general we form plurals by adding -s or -es, perhaps after altering the spelling, according to specific rules. But we generally do not use an apostrophe.
The exception to that rule, however, is that we do use an apostrophe when we pluralize a word (or a letter, number, or symbol) that refers to itself. In these cases it’s also acceptable to omit the apostrophe if the result is clear and unambiguous.
Examples:
YES: This sentence employs two a's, two c's, two d's, twenty-eight e's, five f's, three g's, eight h's, eleven i's, three l's, two m's, thirteen n's, nine o's, two p's, five r's, twenty-five s's, twenty-three t's, six v's, ten w's, two x's, five y's, and one z. (
Source)
NO: H̶i̶s̶ ̶h̶a̶n̶d̶w̶r̶i̶t̶i̶n̶g̶ ̶m̶a̶k̶e̶s̶ ̶i̶t̶ ̶h̶a̶r̶d̶ ̶t̶o̶ ̶d̶i̶s̶t̶i̶n̶g̶u̶i̶s̶h̶ ̶b̶e̶t̶w̶e̶e̶n̶ ̶h̶i̶s̶ ̶a̶s̶ ̶a̶n̶d̶ ̶u̶s̶.̶
YES: I think that that sentence has one too many that’s.
YES: I think that that sentence has one too many thats.
YES: My friend was in his 60s in the ‘60s.
YES: I quit studying grammar because there are too many do’s and dont’s.
YES: I quit studying grammar because there are too many DO’s and DON’T’s.
YES: I quit studying grammar because there are too many DOs and DON’Ts.
NO: I̶ ̶q̶u̶i̶t̶ ̶s̶t̶u̶d̶y̶i̶n̶g̶ ̶g̶r̶a̶m̶m̶a̶r̶ ̶b̶e̶c̶a̶u̶s̶e̶ ̶t̶h̶e̶r̶e̶ ̶a̶r̶e̶ ̶t̶o̶o̶ ̶m̶a̶n̶y̶ ̶d̶o̶s̶ ̶a̶n̶d̶ ̶d̶o̶n̶'̶t̶s̶.̶