diff --git a/code_study/Baekjoon/js/11653.js b/code_study/Baekjoon/js/11653.js
new file mode 100644
index 0000000..c299afb
--- /dev/null
+++ b/code_study/Baekjoon/js/11653.js
@@ -0,0 +1,12 @@
+let N = Number(require("fs").readFileSync(0,"utf8").toString().trim());
+
+let n=2;
+while(N!==1) {
+    if(N%n===0) {
+        console.log(n);
+        N /= n;
+    }
+    else {
+        n++;
+    }
+}
\ No newline at end of file
diff --git a/code_study/Baekjoon/js/1978.js b/code_study/Baekjoon/js/1978.js
new file mode 100644
index 0000000..abcafdd
--- /dev/null
+++ b/code_study/Baekjoon/js/1978.js
@@ -0,0 +1,19 @@
+const s = require("fs").readFileSync(0,"utf8").toString().trim().split('\n');
+const num = s[1].split(' ').map(Number);
+let count = 0;
+
+for(let n of num) {
+    if(n==1) continue;
+    let isPrime = true;
+
+    for(let i=2; i*i<=n; i++){
+        if(n%i==0){
+            isPrime = false;
+            break;
+        }
+    }
+
+    if(isPrime) count++;
+}
+
+console.log(count);
\ No newline at end of file
diff --git a/code_study/Baekjoon/js/2501.js b/code_study/Baekjoon/js/2501.js
new file mode 100644
index 0000000..8ea073b
--- /dev/null
+++ b/code_study/Baekjoon/js/2501.js
@@ -0,0 +1,12 @@
+let [n, k] = require("fs").readFileSync(0,"utf8").toString().trim().split(' ').map(Number);
+let i=1;
+while(i<=n){
+    if(n%i==0) {
+        k--;
+        if(k==0) break;
+    }
+    i++;
+}
+
+if(k!=0) console.log(0);
+else console.log(i);
\ No newline at end of file
diff --git a/code_study/Baekjoon/js/2581.js b/code_study/Baekjoon/js/2581.js
new file mode 100644
index 0000000..66b4703
--- /dev/null
+++ b/code_study/Baekjoon/js/2581.js
@@ -0,0 +1,27 @@
+const [m, n] = require("fs").readFileSync(0,"utf8").toString().trim().split('\n').map(Number);
+let min = 0, sum = 0;
+
+for(let num=m; num<=n; num++) {
+    if(num === 1) continue;
+
+    let isPrime = true;
+    for(let i=2; i*i<=num; i++) {
+        if(num%i==0) {
+            isPrime = false;
+            break;
+        }
+    }
+
+    if(isPrime) {
+        if(min==0) {
+            min = num;
+        }
+        sum += num;
+    }
+}
+
+if(sum===0) console.log(-1);
+else { 
+    console.log(sum);
+    console.log(min);
+}
\ No newline at end of file
diff --git a/code_study/Baekjoon/js/5086.js b/code_study/Baekjoon/js/5086.js
new file mode 100644
index 0000000..f8cc9ba
--- /dev/null
+++ b/code_study/Baekjoon/js/5086.js
@@ -0,0 +1,7 @@
+const n = require("fs").readFileSync(0,"utf8").toString().trim().split('\n');
+let i=0;
+while(true) {
+    let [a, b] = n[i++].split(' ').map(Number);
+    if(a==0 && b==0) break;
+    console.log((b%a==0) ? "factor" : (a%b==0) ? "multiple" : "neither");
+}
\ No newline at end of file
diff --git a/code_study/Baekjoon/js/9506.js b/code_study/Baekjoon/js/9506.js
new file mode 100644
index 0000000..1250fe6
--- /dev/null
+++ b/code_study/Baekjoon/js/9506.js
@@ -0,0 +1,21 @@
+const n = require("fs").readFileSync(0, "utf8").toString().trim().split('\n').map(Number);
+for(let s of n) {
+    if(s==-1) break;
+    let str = [];
+    let sum = 0;
+
+    for(let i=1; i<=s/2; i++) {
+        if(s%i==0) {
+            sum += i;
+            str.push(i);
+        }
+    }
+
+    if(sum===s) {
+        str = s.toString() + " = " + str.join(" + ");
+    }
+    else {
+        str = s.toString() + " is NOT perfect."
+    }
+    console.log(str);
+}
\ No newline at end of file