diff --git a/calculator/test.js b/calculator/test.js
index 7852334..12b114a 100644
--- a/calculator/test.js
+++ b/calculator/test.js
@@ -199,7 +199,11 @@ const finiteTestNumbers = testNumbers.filter(n => isFinite(n));
 
 // Helper to press a number, handling negatives
 function pressNumber(n) {
-  const s = String(n);
+  let s = String(n);
+  // If string representation is in scientific notation, convert to decimal string
+  if (s.includes('e')) {
+    s = n.toFixed(20).replace(/0+$/, '').replace(/\.$/, '');
+  }
   if (s.startsWith('-')) {
     press(s.substring(1));
     buttonPress('N');