Reduce a number and add thousand, million, billion, trillion, quadrillion, ... return an object with the number and the scale

convert_number_to_scale.js

function numberToScale(number) {
  const scales = [
    '',
    'thousand',
    'million',
    'billion',
    'trillion',
    'quadrillion',
    'quintillion',
    'sextillion',
    'septillion',
    'octillion',
    'nonillion',
  ];

  if (number === 0) {
    return { number: 0, scale: '' };
  }

  const i = parseInt(Math.floor(Math.log(number) / Math.log(1000)), 10);

  if (i === 0) {
    return { number: parseFloat(number), scale: scales[i] };
  }

  return {
    number: parseFloat((number / 1000 ** i).toFixed(1)),
    scale: scales[i],
  };
}