JSFiddle - React, Tailwind, and code Playground

HTML

Sum of first <input id="primeSumCount" type="number" value="1000" min="1" max="100000"> primes is <span id="primeSumAnswer"></span>

JavaScript

$( function() {
    var countEl = $( '#primeSumCount' ),
       sumEl = $( '#primeSumAnswer' );
    
    countEl.on( 'input', updateSum );
    
    function updateSum() {
        var n = countEl.val(),
            sum = sumPrimes( n );
        
        sumEl.text( sum );
    }
    
    function sumPrimes( n ) {
        var primes = [ 2 ],
            pLen = primes.length;

        for ( var i = primes[ pLen - 1 ] + 1; pLen < n; i += 2 ) {
            var isPrime = true;
            for ( var j = 0; j < pLen; j++ ) {
                if ( i % primes[ j ] === 0 ) {
                    isPrime = false;
                    break;
                }
            }
            if ( isPrime ) {
                pLen++;
                primes.push( i );
            }
        }
        
        return primes.slice( 0, n ).reduce( function ( a, b ) {
            return a + b
        }, 0 )
    }
    
    updateSum();
} );