text: var checkSquareNumber = function checkSquareNumber(number, callback) {
    let result;
    if (isNaN(number)) {
      var err = new Error('is not number');
      return callback(err);
    }
  
    if (number <= 0) {
      result = false;
      return callback(null, result);
    }
  
    let i = Math.sqrt(number);
    if (number === i * i) {
      result = true;
    } else {
      result = false;
    }
  
    return callback(null, result);
  };
  
  module.exports = {
    checkSquareNumber
  };
  