diff --git a/dist/index.esm.js b/dist/index.esm.js
index be41b8a..1a788e4 100644
--- a/dist/index.esm.js
+++ b/dist/index.esm.js
@@ -56,7 +56,7 @@ function encodeTime(now, len) {
     if (now < 0) {
         throw createError("time must be positive");
     }
-    if (Number.isInteger(now) === false) {
+    if (Number.isInteger(Number(now)) === false) {
         throw createError("time must be an integer");
     }
     let mod;
diff --git a/dist/index.js b/dist/index.js
index a7aedbf..86ab99b 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -56,7 +56,7 @@ export function encodeTime(now, len) {
     if (now < 0) {
         throw createError("time must be positive");
     }
-    if (Number.isInteger(Number(now)) === false) { 
+    if (Number.isInteger(Number(now)) === false) {
         throw createError("time must be an integer");
     }
     let mod;
diff --git a/dist/index.umd.js b/dist/index.umd.js
index 45203a6..9363732 100644
--- a/dist/index.umd.js
+++ b/dist/index.umd.js
@@ -62,7 +62,7 @@
         if (now < 0) {
             throw createError("time must be positive");
         }
-        if (Number.isInteger(now) === false) {
+        if (Number.isInteger(Number(now)) === false) {
             throw createError("time must be an integer");
         }
         let mod;
diff --git a/lib/index.ts b/lib/index.ts
index 0835321..7a83451 100644
--- a/lib/index.ts
+++ b/lib/index.ts
@@ -73,7 +73,7 @@ export function encodeTime(now: number, len: number): string {
   if (now < 0) {
     throw createError("time must be positive")
   }
-  if (Number.isInteger(now) === false) {
+  if (Number.isInteger(Number(now)) === false) {
     throw createError("time must be an integer")
   }
   let mod