Integer data types can be specified as follows:
INTEGER INTEGER([KIND=]n) INTEGER*n
If a kind parameter is specified, the integer has the kind specified. If a kind parameter is not specified, integer constants are interpreted as follows:
An integer constant is a whole number with no decimal point. It can have a leading sign and is interpreted as a decimal number.
Integer constants take the following form:
[s]n[n...][ _k]
An unsigned constant is assumed to be nonnegative.
Integers are expressed in decimal values (base 10) by default. To specify a constant that is not in base 10, use the following syntax:
[s][[base] #]nnn...
If base is omitted but # is specified, the integer is interpreted in base 16. If both base and # are omitted, the integer is interpreted in base 10.
For bases 11 through 36, the letters A through Z represent numbers greater than 9. For example, for base 36, A represents 10, B represents 11, C represents 12, and so on, through Z, which represents 35. The case of the letters is not significant.
The following examples show valid and invalid integer (base 10) constants:
Valid  
0  
127  
+32123  
47_2  
Invalid  Explanation 
9999999999999999999 
Number too large. 
3.14
 Decimal point not allowed; this is a valid REAL constant. 
32,767
 Comma not allowed. 
33_3  3 is not a valid kind for integers. 
The following integers (most of which are not base 10) are all assigned a value equal to 3,994,575 decimal:
I = 2#1111001111001111001111 m = 7#45644664 J = +8#17171717 K = #3CF3CF n = +17#2DE110 L = 3994575 index = 36#2DM8F
You can use integer constants to assign values to data. The following table shows assignments to different data and lists the integer and hexadecimal values in the data:
Fortran Assignment  Integer Value in the Data  Hexadecimal Value in the Data 

LOGICAL(1) X INTEGER(1) X 

X = 128  128  Z' 80' 
X = 127  127  Z'
7F' 
X = 255  1  Z' FF'

LOGICAL(2) X INTEGER(2) X  
X = 255  255  Z' FF' 
X = 32768  32768  Z'
8000' 
X = 32767  32767  Z' 7FFF'

X = 65535   1  Z' FFFF' 