diff --git a/algorithms/src/main/java/com/baeldung/algorithms/primechecker/BigIntegerPrimeChecker.java b/algorithms/src/main/java/com/baeldung/algorithms/primechecker/BigIntegerPrimeChecker.java
index bd4708b661..752e659fa3 100644
--- a/algorithms/src/main/java/com/baeldung/algorithms/primechecker/BigIntegerPrimeChecker.java
+++ b/algorithms/src/main/java/com/baeldung/algorithms/primechecker/BigIntegerPrimeChecker.java
@@ -2,10 +2,10 @@ package com.baeldung.algorithms.primechecker;
 
 import java.math.BigInteger;
 
-public class BigIntegerPrimeChecker implements PrimeChecker{
+public class BigIntegerPrimeChecker implements PrimeChecker<Long>{
 
     @Override
-    public boolean isPrime(int number) {
+    public boolean isPrime(Long number) {
         BigInteger bigInt = BigInteger.valueOf(number);
         return bigInt.isProbablePrime(100);
     }
diff --git a/algorithms/src/main/java/com/baeldung/algorithms/primechecker/BruteForcePrimeChecker.java b/algorithms/src/main/java/com/baeldung/algorithms/primechecker/BruteForcePrimeChecker.java
index 0dfcfa1505..47ffb3e224 100644
--- a/algorithms/src/main/java/com/baeldung/algorithms/primechecker/BruteForcePrimeChecker.java
+++ b/algorithms/src/main/java/com/baeldung/algorithms/primechecker/BruteForcePrimeChecker.java
@@ -1,12 +1,15 @@
 package com.baeldung.algorithms.primechecker;
 
 import java.util.stream.IntStream;
+import java.util.stream.LongStream;
 
-public class BruteForcePrimeChecker implements PrimeChecker{
+public class BruteForcePrimeChecker implements PrimeChecker<Integer>{
 
     @Override
-    public boolean isPrime(int number) {
-        return IntStream.range(2, number).noneMatch(n -> (number % n == 0));
+    public boolean isPrime(Integer number) {
+        
+        return number > 2 ? IntStream.range(2, number)
+            .noneMatch(n -> (number % n == 0)) : false;
     }
 
     
diff --git a/algorithms/src/main/java/com/baeldung/algorithms/primechecker/OptimisedPrimeChecker.java b/algorithms/src/main/java/com/baeldung/algorithms/primechecker/OptimisedPrimeChecker.java
index f7e3e09be0..06ae4acc7f 100644
--- a/algorithms/src/main/java/com/baeldung/algorithms/primechecker/OptimisedPrimeChecker.java
+++ b/algorithms/src/main/java/com/baeldung/algorithms/primechecker/OptimisedPrimeChecker.java
@@ -1,13 +1,14 @@
 package com.baeldung.algorithms.primechecker;
 
 import java.util.stream.IntStream;
+import java.util.stream.LongStream;
 
-public class OptimisedPrimeChecker implements PrimeChecker{
+public class OptimisedPrimeChecker implements PrimeChecker<Integer>{
 
     @Override
-    public boolean isPrime(int number) {
-        return IntStream.range(2, (int)Math.sqrt(number) + 1)
-            .noneMatch(n -> (number % n == 0));
+    public boolean isPrime(Integer number) {
+        return number > 2 ? IntStream.rangeClosed(2, (int) Math.sqrt(number))
+            .noneMatch(n -> (number % n == 0)) : false;
     }
 
     
diff --git a/algorithms/src/main/java/com/baeldung/algorithms/primechecker/PrimeChecker.java b/algorithms/src/main/java/com/baeldung/algorithms/primechecker/PrimeChecker.java
index f31af1ca4f..5f7a15a939 100644
--- a/algorithms/src/main/java/com/baeldung/algorithms/primechecker/PrimeChecker.java
+++ b/algorithms/src/main/java/com/baeldung/algorithms/primechecker/PrimeChecker.java
@@ -1,6 +1,6 @@
 package com.baeldung.algorithms.primechecker;
 
-public interface PrimeChecker {
+public interface PrimeChecker <T> {
     
-    public boolean isPrime( int number );
+    public boolean isPrime( T number );
 }
diff --git a/algorithms/src/main/java/com/baeldung/algorithms/primechecker/PrimesPrimeChecker.java b/algorithms/src/main/java/com/baeldung/algorithms/primechecker/PrimesPrimeChecker.java
index ee66d5d2ab..08b095cb79 100644
--- a/algorithms/src/main/java/com/baeldung/algorithms/primechecker/PrimesPrimeChecker.java
+++ b/algorithms/src/main/java/com/baeldung/algorithms/primechecker/PrimesPrimeChecker.java
@@ -2,10 +2,10 @@ package com.baeldung.algorithms.primechecker;
 
 import org.apache.commons.math3.primes.Primes;
 
-public class PrimesPrimeChecker implements PrimeChecker{
+public class PrimesPrimeChecker implements PrimeChecker<Integer>{
 
     @Override
-    public boolean isPrime(int number) {
+    public boolean isPrime(Integer number) {
         return Primes.isPrime(number);
     }
 
diff --git a/algorithms/src/test/java/com/baeldung/algorithms/primechecker/BigIntegerPrimeCheckerTest.java b/algorithms/src/test/java/com/baeldung/algorithms/primechecker/BigIntegerPrimeCheckerTest.java
index 95eb85749d..8980397c68 100644
--- a/algorithms/src/test/java/com/baeldung/algorithms/primechecker/BigIntegerPrimeCheckerTest.java
+++ b/algorithms/src/test/java/com/baeldung/algorithms/primechecker/BigIntegerPrimeCheckerTest.java
@@ -9,18 +9,20 @@ import com.baeldung.algorithms.primechecker.PrimeChecker;
 
 public class BigIntegerPrimeCheckerTest {
 
-    PrimeChecker primeChecker = new BigIntegerPrimeChecker();
+    BigIntegerPrimeChecker primeChecker = new BigIntegerPrimeChecker();
     
     @Test
     public void givenPrimeNumber_whenCheckIsPrime_thenTrue(){
-        assertTrue(primeChecker.isPrime(13));
-        assertTrue(primeChecker.isPrime(1009));
+        assertTrue(primeChecker.isPrime(13l));
+        assertTrue(primeChecker.isPrime(1009L));
+        assertTrue(primeChecker.isPrime(74207281L));
     }
     
     @Test
     public void givenNonPrimeNumber_whenCheckIsPrime_thenFalse(){
-        assertTrue(!primeChecker.isPrime(50));
-        assertTrue(!primeChecker.isPrime(1001));
+        assertTrue(!primeChecker.isPrime(50L));
+        assertTrue(!primeChecker.isPrime(1001L));
+        assertTrue(!primeChecker.isPrime(74207282L));
     }
     
 }
diff --git a/algorithms/src/test/java/com/baeldung/algorithms/primechecker/OptimisedPrimeCheckerTest.java b/algorithms/src/test/java/com/baeldung/algorithms/primechecker/OptimisedPrimeCheckerTest.java
index 21ad55467f..64ecae7cc3 100644
--- a/algorithms/src/test/java/com/baeldung/algorithms/primechecker/OptimisedPrimeCheckerTest.java
+++ b/algorithms/src/test/java/com/baeldung/algorithms/primechecker/OptimisedPrimeCheckerTest.java
@@ -9,7 +9,7 @@ import com.baeldung.algorithms.primechecker.PrimeChecker;
 
 public class OptimisedPrimeCheckerTest {
 
-    PrimeChecker primeChecker = new OptimisedPrimeChecker();
+    OptimisedPrimeChecker primeChecker = new OptimisedPrimeChecker();
     
     @Test
     public void givenPrimeNumber_whenCheckIsPrime_thenTrue(){
diff --git a/algorithms/src/test/java/com/baeldung/algorithms/primechecker/PrimesPrimeCheckerTest.java b/algorithms/src/test/java/com/baeldung/algorithms/primechecker/PrimesPrimeCheckerTest.java
index 63de593b44..cb294d6643 100644
--- a/algorithms/src/test/java/com/baeldung/algorithms/primechecker/PrimesPrimeCheckerTest.java
+++ b/algorithms/src/test/java/com/baeldung/algorithms/primechecker/PrimesPrimeCheckerTest.java
@@ -8,7 +8,7 @@ import com.baeldung.algorithms.primechecker.PrimeChecker;
 import com.baeldung.algorithms.primechecker.PrimesPrimeChecker;
 
 public class PrimesPrimeCheckerTest {
-    PrimeChecker primeChecker = new PrimesPrimeChecker();
+    PrimesPrimeChecker primeChecker = new PrimesPrimeChecker();
 
     @Test
     public void givenPrimeNumber_whenCheckIsPrime_thenTrue() {