diff --git a/src/Reflection/InitializerExprTypeResolver.php b/src/Reflection/InitializerExprTypeResolver.php
index 8b38c5a383..008e3785fc 100644
--- a/src/Reflection/InitializerExprTypeResolver.php
+++ b/src/Reflection/InitializerExprTypeResolver.php
@@ -91,6 +91,7 @@
 use function max;
 use function min;
 use function sprintf;
+use function str_starts_with;
 use function strtolower;
 use const INF;
 
@@ -506,6 +507,10 @@ public function resolveConcatType(Type $left, Type $right): Type
 
 		$leftNumericStringNonEmpty = TypeCombinator::remove($leftStringType, new ConstantStringType(''));
 		if ($leftNumericStringNonEmpty->isNumericString()->yes()) {
+			$validationCallback = $left->isInteger()->yes()
+				? static fn (string $value): bool => !str_starts_with($value, '-')
+				: static fn (string $value): bool => Strings::match($value, '#^\d+$#') !== null;
+
 			$allRightConstantsZeroOrMore = false;
 			foreach ($rightConstantStrings as $rightConstantString) {
 				if ($rightConstantString->getValue() === '') {
@@ -514,7 +519,7 @@ public function resolveConcatType(Type $left, Type $right): Type
 
 				if (
 					!is_numeric($rightConstantString->getValue())
-					|| Strings::match($rightConstantString->getValue(), '#^[0-9]+$#') === null
+					|| !$validationCallback($rightConstantString->getValue())
 				) {
 					$allRightConstantsZeroOrMore = false;
 					break;
diff --git a/tests/PHPStan/Analyser/nsrt/bug-11129.php b/tests/PHPStan/Analyser/nsrt/bug-11129.php
index a845bf1d2a..33007584be 100644
--- a/tests/PHPStan/Analyser/nsrt/bug-11129.php
+++ b/tests/PHPStan/Analyser/nsrt/bug-11129.php
@@ -48,9 +48,20 @@ public function foo(
 		assertType('lowercase-string&non-falsy-string', $i.$maybeNonNumericConstStrings);
 		assertType('lowercase-string&non-falsy-string', $maybeNonNumericConstStrings.$i);
 
-		assertType('lowercase-string&non-falsy-string&uppercase-string', $i.$maybeFloatConstStrings); // could be 'lowercase-string&non-falsy-string&numeric-string'
+		assertType('lowercase-string&non-falsy-string&numeric-string&uppercase-string', $i.$maybeFloatConstStrings);
 		assertType('lowercase-string&non-falsy-string&uppercase-string', $maybeFloatConstStrings.$i);
 
+		assertType('lowercase-string&non-falsy-string&numeric-string&uppercase-string', $i.'1');
+		assertType('lowercase-string&non-falsy-string&numeric-string&uppercase-string', $i.'1.0');
+		assertType('lowercase-string&non-falsy-string&uppercase-string', $i.'1.1.1');
+		assertType('lowercase-string&non-falsy-string&uppercase-string', $i.'-1');
+		assertType('lowercase-string&non-falsy-string&uppercase-string', $i.'-1.0');
+		assertType('lowercase-string&non-falsy-string&numeric-string', $i.'10e-3');
+		assertType('lowercase-string&non-falsy-string', $i.'-10e-3');
+		assertType('non-falsy-string&numeric-string&uppercase-string', $i.'10E3');
+		assertType('non-falsy-string&uppercase-string', $i.'-10E3');
+		assertType('non-falsy-string', $i.'10eE3');
+
 		assertType('lowercase-string&non-empty-string&numeric-string&uppercase-string', $i.$bool);
 		assertType('lowercase-string&non-empty-string&uppercase-string', $bool.$i);
 		assertType('lowercase-string&non-falsy-string&numeric-string&uppercase-string', $positiveInt.$bool);
@@ -68,14 +79,14 @@ public function foo(
 		assertType('non-falsy-string&numeric-string&uppercase-string', $float.$positiveInt);
 		assertType('non-falsy-string&uppercase-string', $float.$negativeInt);
 		assertType('non-falsy-string&uppercase-string', $float.$i);
-		assertType('non-falsy-string&uppercase-string', $i.$float); // could be 'non-falsy-string&numeric-string&uppercase-string'
+		assertType('non-falsy-string&uppercase-string', $i.$float);
 		assertType('non-falsy-string', $numericString.$float);
 		assertType('non-falsy-string', $numericString.$maybeFloatConstStrings);
 
 		// https://3v4l.org/Ia4r0
 		$scientificFloatAsString = '3e4';
 		assertType('non-falsy-string', $numericString.$scientificFloatAsString);
-		assertType('lowercase-string&non-falsy-string', $i.$scientificFloatAsString);
+		assertType('lowercase-string&non-falsy-string&numeric-string', $i.$scientificFloatAsString);
 		assertType('non-falsy-string', $scientificFloatAsString.$numericString);
 		assertType('lowercase-string&non-falsy-string', $scientificFloatAsString.$i);
 	}