English Numerals - Cardinal Numbers

Cardinal Numbers

Cardinal numbers refer to the size of a group. In English, these words are numerals.

If a number is in the range 21 to 99, and the second digit is not zero, one typically writes the number as two words separated by a hyphen.

In English, the hundreds are perfectly regular, except that the word hundred remains in its singular form regardless of the number preceding it (nevertheless, one may on the other hand say "hundreds of people flew in", or the like)

So too are the thousands, with the number of thousands followed by the word "thousand"

In American usage, four-digit numbers with non-zero hundreds are often named using multiples of "hundred" and combined with tens and ones: "One thousand one", "Eleven hundred three", "Twelve hundred twenty-five", "Four thousand forty-two", or "Ninety-nine hundred ninety-nine." In British usage, this style is common for multiples of 100 between 1,000 and 2,000 (e.g. 1,500 as "fifteen hundred") but not for higher numbers.

Americans may pronounce four-digit numbers with non-zero tens and ones as pairs of two-digit numbers without saying "hundred" and inserting "oh" for zero tens: "twenty-six fifty-nine" or "forty-one oh five". This usage probably evolved from the distinctive usage for years; "nineteen-eighty-one". It is avoided for numbers less than 2500 if the context may mean confusion with time of day: "ten ten" or "twelve oh four".

Intermediate numbers are read differently depending on their use. Their typical naming occurs when the numbers are used for counting. Another way is for when they are used as labels. The second column method is used much more often in American English than British English. The third column is used in British English, but rarely in American English (although the use of the second and third columns is not necessarily directly interchangeable between the two regional variants). In other words, British English and American English can seemingly agree, but it depends on a specific situation (in this example, bus numbers).

Note: When writing a cheque (or check), the number 100 is always written "one hundred". It is never "a hundred".

Note that in American English, many students are taught not to use the word and anywhere in the whole part of a number, so it is not used before the tens and ones. It is instead used as a verbal delimiter when dealing with compound numbers. Thus, instead of "three hundred and seventy-three", one would say "three hundred seventy-three". For details, see American and British English differences.

For numbers above a million, there are two different systems for naming numbers in English (for the use of prefixes such as kilo- for a thousand, mega- for a million, milli- for a thousandth, etc. see SI units):

• the long scale (decreasingly used in British English) designates a system of numeric names in which a thousand million is called a ‘‘milliard’’ (but the latter usage is now rare), and ‘‘billion’’ is used for a million million.
• the short scale (always used in American English and increasingly in British English) designates a system of numeric names in which a thousand million is called a ‘‘billion’’, and the word ‘‘milliard’’ is not used.

The numbers past a trillion, in ascending powers of ten, are as follows: quadrillion, quintillion, sextillion, septillion, octillion, nonillion, decillion, undecillion, duodecillion, tredecillion, quattuordecillion, and quindecillion (that's 10 to the 48th, or a one followed by 48 zeros). The highest number listed on Robert Munafo's table, is a milli-millillion. That's 10 to the 3000003rd.

The googolplex has often been nominated as the largest named number in the world. If a googol is ten to the one hundredth, then a googolplex is one followed by a googol of zeroes.

Although British English has traditionally followed the long-scale numbering system, the short-scale usage has become increasingly common in recent years. For example, the UK Government and BBC websites use the newer short-scale values exclusively.

The terms arab, kharab, padm and shankh are more commonly found in old sections of Indian Mathematics.

Here are some approximate composite large numbers in American English:

Often, large numbers are written with (preferably non-breaking) half-spaces or thin spaces separating the thousands (and, sometimes, with normal spaces or apostrophes) instead of commas—to ensure that confusion is not caused in countries where a decimal comma is used. Thus, a million is often written 1 000 000.

In some areas, a point (. or ·) may also be used as a thousands' separator, but then, the decimal separator must be a comma.