Numeral systems by culture  

Hindu–Arabic numerals  
Western Arabic Eastern Arabic Khmer 
Indian family Brahmi Thai 
East Asian numerals  
Chinese Suzhou Counting rods 
Japanese Korean 
Alphabetic numerals  
Abjad Armenian Cyrillic Ge'ez 
Hebrew Greek (Ionian) Āryabhaṭa 
Other systems  
Attic Babylonian Egyptian Etruscan 
Mayan Roman Urnfield 
List of numeral system topics  
Positional systems by base  
Decimal (10)  
2, 4, 8, 16, 32, 64  
1, 3, 9, 12, 20, 24, 30, 36, 60, more…  
Greek numerals are a system of representing numbers using letters of the Greek alphabet. They are also known by the names Milesian numerals, Alexandrian numerals, or alphabetic numerals. In modern Greece, they are still in use for ordinal numbers, and in much of the same way that Roman numerals are in the West; for ordinary (cardinal) numbers, Arabic numerals are used.
At first, before it was used more, the Greek alphabet, Linear A and Linear B had used a different system with symbols for 1, 10, 100, 1000 and 10000 operating with the following formula:  = 1, – = 10, ◦ = 100, ¤ = 1000, ☼ = 10000.
The earliest alphabetrelated system of numerals used with the Greek letters was a set of the acrophonic Attic numerals, operating much like Roman numerals (which derived from this scheme), with the following formula: Ι = 1, Π = 5, Δ = 10, ΠΔ = 50, Η = 100, ΠΗ = 500, Χ = 1000, ΠΧ = 5000, Μ = 10000 and ΠΜ = 50000.
The acrophonic system was replaced by a new alphabetic system, sometimes called the Ionic numeral system, from the 4th century BC. Each unit (1, 2, …, 9) was assigned a separate letter, each tens (10, 20, …, 90) a separate letter, and each hundreds (100, 200, …, 900) a separate letter. This requires 27 letters, so the 24letter Greek alphabet was extended by using three obsolete letters: fau ϝ, (also used are stigma ϛ or, in modern Greek, στ) for 6, qoppa ϟ for 90, and sampi ϡ for 900. To distinguish numerals from letters they are followed by the "keraia" (Greek κεραία—insect antenna), a symbol similar to an acute sign (Unicode U+0374).
This alphabetic system operates on the additive principle in which the numeric values of the letters are added together to form the total. For example, 241 is represented as σμαʹ (200 + 40 + 1).
To represent numbers from 1,000 to 999,999 the same letters are reused to serve as thousands, tens of thousands, and hundreds of thousands. A "left keraia" (Unicode U+0375, ‘Greek Lower Numeral Sign’) is put in front of thousands to distinguish them from the standard use. For example, 2008 is represented as ͵βηʹ (2000 + 8).
Letter  Value  Letter  Value  Letter  Value  

αʹ  1  ιʹ  10  ρʹ  100  
βʹ  2  κʹ  20  σʹ  200  
γʹ  3  λʹ  30  τʹ  300  
δʹ  4  μʹ  40  υʹ  400  
εʹ  5  νʹ  50  φʹ  500  
ϛ  6  ξʹ  60  χʹ  600  
ζʹ  7  οʹ  70  ψʹ  700  
ηʹ  8  πʹ  80  ωʹ  800  
θʹ  9  ϟʹ  90  ϡʹ  900 
In modern Greek, uppercase letters are used more, as in Φίλιππος Βʹ = Philip II.
Higher numbers
The Greeks also used the myriad to denote 10,000 (Μʹ) and the myriad myriad for one hundred million (ΜΜʹ).
Decimal  Symbol  Greek numeral 

1  Ι  ena 
5  Π  πέντε (peda) 
10  Δ  δέκα (deka) 
100  Η  ἧκατόν (hekaton) 
1000  Χ  χίλιοι (khilioi) 
10000  Μ  μύριοι (myrioi) 
Images for kids

A 14thcentury Byzantine map of the British Isles from a manuscript of Ptolemy's Geography, using Greek numerals for its graticule: 52–63°N of the equator and 6–33°E from Ptolemy's Prime Meridian at the Fortunate Isles.