Do not crash on NaN, and provide default

packages/website/ts/utils/utils.ts

@@ -28,8 +28,8 @@ import {
 } from 'ts/types';
 import { configs } from 'ts/utils/configs';
 import { constants } from 'ts/utils/constants';
+import { errorReporter } from 'ts/utils/error_reporter';
 import * as u2f from 'ts/vendor/u2f_api';
-import { errorReporter } from './error_reporter';
 
 const isDogfood = (): boolean => _.includes(window.location.href, configs.DOMAIN_DOGFOOD);
 
@@ -391,7 +391,11 @@ export const utils = {
         const format = `0,0.${_.repeat('0', precision)}`;
         const formattedAmount = numeral(unitAmount).format(format);
         if (_.isNaN(formattedAmount)) {
-            throw new Error(`amount ${BigNumber}, decimals ${decimals} could not be formatted and returned NaN.`);
+            // tslint:disable-next-line:no-floating-promises
+            errorReporter.reportAsync(
+                new Error(`amount ${BigNumber}, decimals ${decimals} could not be formatted and returned NaN.`),
+            );
+            return format;
         }
         return formattedAmount;
     },