/**
 * Formats a number with a specified number of decimal places.
 *
 * @param number - The number to format. It can be a number, bigint, string, or undefined.
 * @param maximumFractionDigits - The maximum number of decimal places to display (default: 2).
 * @param locale - The locale to use for formatting the number (optional).
 * @param roundingModeParam - The rounding mode to use for formatting (default: 'floor').
 * @returns The formatted number string.
 */
export declare const formatNumber: (number: number | bigint | string | undefined, maximumFractionDigits?: number, locale?: string, roundingModeParam?: string) => string;