Number 28

Representations of 28
Greek numeral
κηʹ
Sanskrit numeral
२८
Arabic numeral
٢٨
Roman numeral
XXVIII
Maya numeral
●
●●●
▃▃▃▃▃
Chinese numeral
二十八
Hebrew numeral
כח
28 in different numeral systems
Binary
11100
Base-3
1001
Base-4
130
Base-5
103
Base-6
44
Base-7
40
Base-8
34
Duodecimal
24
Hex
1c
Vigesimal
18
Base-24
14
Base-36
s
Negabinary
1101100
Factorization
Prime factors
2, 7
Divisors
1, 2, 4, 7, 14, 28
Sum of divisors other than 28
28 Perfect number
Product of prime factors
28 = 2 x 2 x 7
Characteristics
Triangular Hexagonal Difference of 2 squares Even Ones-Zeroes Composite Perfect
Related primes
Number 28 prime
107
Prime number before 28
23
Prime number after 28
29