これでどうでしょう?
javascript
1new Date(Date.parse("2021/04/20 17:41:28")).getFullYear();
2> 2021
3new Date(Date.parse("2021/04/20 17:41:28")).getMonth()+1;
4> 4
5new Date(Date.parse("2021/04/20 17:41:28")).getDate();
6>20
7new Date(Date.parse("2021/04/20 17:41:28")).getHours();
8> 17
9new Date(Date.parse("2021/04/20 17:41:28")).getMinutes();
10> 41
11new Date(Date.parse("2021/04/20 17:41:28")).getSeconds();
12> 28