diff --git a/libraries/ESP32/examples/DeepSleep/TimerWakeUp/TimerWakeUp.ino b/libraries/ESP32/examples/DeepSleep/TimerWakeUp/TimerWakeUp.ino
index e8f280f3..ec43cf72 100644
--- a/libraries/ESP32/examples/DeepSleep/TimerWakeUp/TimerWakeUp.ino
+++ b/libraries/ESP32/examples/DeepSleep/TimerWakeUp/TimerWakeUp.ino
@@ -19,7 +19,7 @@ Author:
 Pranav Cherukupalli <cherukupallip@gmail.com>
 */
 
-#define uS_TO_S_FACTOR 1000000  /* Conversion factor for micro seconds to seconds */
+#define uS_TO_S_FACTOR 1000000ULL  /* Conversion factor for micro seconds to seconds */
 #define TIME_TO_SLEEP  5        /* Time ESP32 will go to sleep (in seconds) */
 
 RTC_DATA_ATTR int bootCount = 0;