Number 18

Representations of 18
Greek numeral
ιηʹ
Arabic numeral
١٨
Roman numeral
XVIII
Maya numeral
●●●
▃▃▃▃▃
▃▃▃▃▃
▃▃▃▃▃
Chinese numeral
十八
Hebrew numeral
חי
18 in different numeral systems
Binary
10010
Base-3
200
Base-4
102
Base-5
33
Base-6
30
Base-7
24
Base-8
22
Hex
12
Base-24
i
Base-36
i
Factorization
Prime factors
2, 3
Divisors
1, 2, 3, 6, 9, 18
Sum of divisors other than 18
21
Product of prime factors
18 = 2 x 3 x 3
Characteristics
Heptagonal Even Composite
Related primes
Number 18 prime
61
Prime number before 18
17
Prime number after 18
19