74,138
The 74138 is a three-to-eight line decoder.
- Even
- Composite
Where 74,138 fits
Why 74,138 is special
It turns three address lines into eight chip-select signals, which is how a computer with one bus decides which memory or peripheral is being addressed.
74,138 is part of
Factors & digit properties
- Divisors (8)
- 1, 2, 19, 38, 1951, 3902, 37069, 74138
- Prime factorisation
- 2 × 19 × 1951
- Digit sum
- 23
- Digital root
- 5
Representations
- Decimal
- 74138
- Scientific notation
- 7.414 × 10^4
Roman numerals
Roman numerals as modelled here goes up to 3,999.
Binary
1 0 0 1 0 0 0 0 1 1 0 0 1 1 0 1 0
1 × 65,536 + 0 × 32,768 + 0 × 16,384 + 1 × 8,192 + 0 × 4,096 + 0 × 2,048 + 0 × 1,024 + 0 × 512 + 1 × 256 + 1 × 128 + 0 × 64 + 0 × 32 + 1 × 16 + 1 × 8 + 0 × 4 + 1 × 2 + 0 × 1 = 74,138
Octal
2 2 0 6 3 2
2 × 32,768 + 2 × 4,096 + 0 × 512 + 6 × 64 + 3 × 8 + 2 × 1 = 74,138
Hexadecimal
1 2 1 9 a
1 × 65,536 + 2 × 4,096 + 1 × 256 + 9 × 16 + a × 1 = 74,138
Read as powers of two: 65,536 + 8,192 + 256 + 128 + 16 + 8 + 2 = 74,138.
In historical numeral systems
Egyptian
7 fingers, 4 lotuses, 1 coil of rope, 3 hobbles, 8 strokes
7 × 10,000 + 4 × 1,000 + 1 × 100 + 3 × 10 + 8 × 1 = 74,138. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Systems that simply cannot reach this value are left out. Where a script needs a font most readers do not have, the reading is given instead of the glyphs — see number systems for each system in full.
Other mathematical patterns
- Deficient number
- Happy number
Related numbers & connections
One expands a few pins into many outputs and the other narrows many address lines into one selection, which are opposite jobs on the same bus.
View 74595 →Technology & computing
The 74138 decodes three binary inputs to one of eight active-low outputs with three enable inputs. It is the standard address-decoding part in memory-mapped systems.
DocumentedTechnology & computingPeriod: 1970s–
Common questions
Is 74,138 a prime number?
No, 74,138 is not prime.
What are the factors of 74,138?
The factors of 74,138 are 1, 2, 19, 38, 1951, 3902, 37069, 74138.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 1 reviewer-confirmed record, sourced and reviewed before publication.
Last reviewed: 15 July 2026