Math and Number Utilities

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Last updated: October 2026 · 102 examples

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Topics102
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Program to Find the Sum of Natural NumbersJavaScript Program to Check if the Numbers Have Same Last DigitJavaScript Program to Find HCF or GCDJavaScript Program to Find LCMJavaScript Program to Find the Factors of a NumberJavaScript Program to Find Sum of Natural Numbers Using RecursionJavaScript Program to Guess a Random NumberJavaScript Program to Shuffle Deck of CardsJavaScript Program to Display Fibonacci Sequence Using RecursionJavaScript Program to Find Factorial of Number Using RecursionJavaScript Program to Convert Decimal to BinaryJavaScript Program to Find ASCII Value of CharacterJavaScript Program to Check Whether a String is Palindrome or NotJavaScript Program to Sort Words in Alphabetical OrderJavaScript Program to Replace Characters of a StringJavaScript Program to Reverse a StringJavaScript Program to Create Objects in Different WaysJavaScript Program to Check the Number of Occurrences of a Character in the StringJavaScript Program to Convert the First Letter of a String 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ArrayJavaScript Program to Extract Given Property Values from Objects as ArrayJavaScript Program to Compare Elements of Two ArraysJavaScript Program to Get Random Item From an ArrayJavaScript Program To Perform Intersection Between Two ArraysJavaScript Program to Split Array into Smaller ChunksJavaScript Program to Include a JS file in Another JS fileJavaScript Program to Get File ExtensionJavaScript Program To Check If A Variable Is undefined or nullJavaScript Program to Set a Default Parameter Value For a FunctionJavaScript Program to Illustrate Different Set OperationsJavascript Program to Generate a Random Number Between Two NumbersJavaScript Program To Get The Current URLJavaScript Program to Validate An Email AddressJavaScript Program to Check If a Variable is of Function TypeJavaScript Program To Work With ConstantsJavaScript Program to Pass Parameter to a setTimeout() FunctionJavaScript Program to Generate a Range of Numbers and CharactersJavaScript Program to Perform Function OverloadingJavaScript Program to Implement a StackJavaScript Program to Implement a QueueJavaScript Program to Check if a Number is Float or IntegerJavaScript Program to Pass a Function as ParameterJavaScript Program to Get the Dimensions of an ImageJavaScript Program to Remove All Whitespaces From a TextJavaScript Program to Write to Console
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JavaScript Program to Print the Fibonacci Sequence

Generate the first N Fibonacci numbers.

Source Code
function fib(n){const a=[0,1]; for(let i=2;i<n;i++){a[i]=a[i-1]+a[i-2];} return a.slice(0,n);} console.log(fib(10));
Expected Output
JavaScript Program to Find the Square Root
Compute square root using Math.sqrt.
Source Code
const n=81; console.log(Math.sqrt(n));
Expected Output
JavaScript Program to Check Prime Number
Check divisibility up to sqrt(n).
Source Code
function isPrime(n){if(n<2)return false; for(let i=2;i*i<=n;i++){if(n%i===0)return false;} return true;} console.log(isPrime(29));
Expected Output
JavaScript Program to Print All Prime Numbers in an Interval
List primes in a range.
Source Code
function isPrime(n){if(n<2)return false; for(let i=2;i*i<=n;i++){if(n%i===0)return false;} return true;} const out=[]; for(let n=10;n<=50;n++){if(isPrime(n))out.push(n);} console.log(out.join(", "));
Expected Output
JavaScript Program to Find the Factorial of a Number
Iterative factorial.
Source Code
function fact(n){let f=1; for(let i=2;i<=n;i++){f*=i;} return f;} console.log(fact(5));
Expected Output
JavaScript Program to Display the Multiplication Table
Multiplication table for a number.
Source Code
const n=5; for(let i=1;i<=10;i++){ console.log(n+" x "+i+" = "+(n*i)); }
Expected Output
JavaScript Program to Check Armstrong Number
Check if sum of powered digits equals number.
Source Code
function isArmstrong(n){const s=String(n); const p=s.length; let sum=0; for(const ch of s){sum+=Math.pow(Number(ch),p);} return sum===n;} console.log(isArmstrong(153));
Expected Output
JavaScript Program to Find Armstrong Number in an Interval
List Armstrong numbers in range.
Source Code
function isA(n){const s=String(n); const p=s.length; let sum=0; for(const ch of s){sum+=Math.pow(Number(ch),p);} return sum===n;} const out=[]; for(let n=100;n<=999;n++){if(isA(n))out.push(n);} console.log(out);
Expected Output
JavaScript Program to Find the Sum of Natural Numbers
Sum 1..n.
Source Code
function sumN(n){let s=0; for(let i=1;i<=n;i++){s+=i;} return s;} console.log(sumN(100));
Expected Output
JavaScript Program to Find HCF or GCD
Euclidean algorithm.
Source Code
function gcd(a,b){while(b){[a,b]=[b,a%b];} return a;} console.log(gcd(48,18));
Expected Output
JavaScript Program to Find LCM
LCM using GCD.
Source Code
function gcd(a,b){while(b){[a,b]=[b,a%b];} return a;} function lcm(a,b){return Math.abs(a*b)/gcd(a,b);} console.log(lcm(12,18));
Expected Output
JavaScript Program to Find Sum of Natural Numbers Using Recursion
Recursive sum.
Source Code
function sumN(n){return n<=1?n: n+sumN(n-1);} console.log(sumN(10));
Expected Output
JavaScript Program to Display Fibonacci Sequence Using Recursion
Recursive Fibonacci.
Source Code
function fib(n){return n<2?n: fib(n-1)+fib(n-2);} console.log(Array.from({length:10},(_,i)=>fib(i)));
Expected Output
JavaScript Program to Find Factorial of Number Using Recursion
Recursive factorial.
Source Code
function fact(n){return n<=1?1:n*fact(n-1);} console.log(fact(6));
Expected Output
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