diff --git a/src/Psalm/Internal/Analyzer/Statements/Expression/BinaryOp/NonDivArithmeticOpAnalyzer.php b/src/Psalm/Internal/Analyzer/Statements/Expression/BinaryOp/NonDivArithmeticOpAnalyzer.php
index 83d11e83b..19b90246f 100644
--- a/src/Psalm/Internal/Analyzer/Statements/Expression/BinaryOp/NonDivArithmeticOpAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/Statements/Expression/BinaryOp/NonDivArithmeticOpAnalyzer.php
@@ -37,6 +37,7 @@ use function array_values;
 use function preg_match;
 use function strtolower;
 use function is_int;
+use const PHP_INT_MAX;
 
 /**
  * @internal
@@ -312,7 +313,12 @@ class NonDivArithmeticOpAnalyzer
             } elseif ($parent instanceof PhpParser\Node\Expr\BinaryOp\Mod) {
                 $calculated_type = Type::getInt(false, $left_type_part->value % $right_type_part->value);
             } elseif ($parent instanceof PhpParser\Node\Expr\BinaryOp\Mul) {
-                $calculated_type = Type::getInt(false, $left_type_part->value * $right_type_part->value);
+                $result = $left_type_part->value * $right_type_part->value;
+                if ($result <= PHP_INT_MAX) {
+                    $calculated_type = Type::getInt(false, $result);
+                } else {
+                    $calculated_type = Type::getFloat($result);
+                }
             } elseif ($parent instanceof PhpParser\Node\Expr\BinaryOp\Pow) {
                 $calculated_type = Type::getInt(false, $left_type_part->value ** $right_type_part->value);
             } elseif ($parent instanceof PhpParser\Node\Expr\BinaryOp\BitwiseOr) {
diff --git a/tests/BinaryOperationTest.php b/tests/BinaryOperationTest.php
index d46ef20f1..4790ea50d 100644
--- a/tests/BinaryOperationTest.php
+++ b/tests/BinaryOperationTest.php
@@ -388,6 +388,13 @@ class BinaryOperationTest extends TestCase
                             echo "Actually, zero\n";
                         }
                     }'
+            ],
+            'IntOverflow' => [
+                '<?php
+                    $a = (1024 * 1024 * 1024 * 1024 * 1024 * 1024 * 1024);',
+                'assertions' => [
+                    '$a' => 'float'
+                ],
             ]
         ];
     }