196
196 is the smallest number suspected never to produce a palindrome by reverse-and-add.
Where 196 fits
Why 196 is special
Reverse the digits, add, repeat: almost every number reaches a palindrome quickly. 196 has been carried past a billion digits without producing one, and no proof exists either way. It is the smallest candidate Lychrel number.
196 is part of
Factors & digit properties
- Divisors (9)
- 1, 2, 4, 7, 14, 28, 49, 98, 196
- Prime factorisation
- 2^2 × 7^2
- Digit sum
- 16
- Digital root
- 7
Representations
- Decimal
- 196
- Scientific notation
- 1.960 × 10^2
Roman numerals
C X C V I
CXCVI uses the subtractive pair XC: ten before a hundred — a hundred minus ten.
Binary
1 1 0 0 0 1 0 0
1 × 128 + 1 × 64 + 0 × 32 + 0 × 16 + 0 × 8 + 1 × 4 + 0 × 2 + 0 × 1 = 196
Octal
3 0 4
3 × 64 + 0 × 8 + 4 × 1 = 196
Hexadecimal
c 4
c × 16 + 4 × 1 = 196
Read as powers of two: 128 + 64 + 4 = 196.
In historical numeral systems
Egyptian
1 coil of rope, 9 hobbles, 6 strokes
1 × 100 + 9 × 10 + 6 × 1 = 196. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
3 vertical wedges (sixties place), 1 corner wedge + 6 vertical wedges (units place)
3 × 60 + 16 = 196. Places are separated by a space on the tablet, with the higher place written first.
Greek (Ionic)
rho, then koppa, then stigma, marked as a numeral
rho-koppa-stigma + keraia
rho + koppa + stigma written in descending order and added — the letters carry their values wherever they stand, so this is addition, not place value.
Hebrew numerals
qof, then tsadi, then vav
qof-tsadi-vav
qof (100) + tsadi (90) + vav (6) = 196, written in descending order.
Maya
1 bar + 4 dots (upper, twenties place) over 3 bars + 1 dot (lower, units place)
9 × 20 + 16 = 196. Places stack vertically with the smallest at the bottom, so the upper group is worth twenty times the lower.
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
- Abundant number
- Powerful number
Related numbers & connections
Both are digit-reversal curiosities. 1089 always works and is a parlour trick; 196 has resisted a billion digits of computation and is an open problem.
View 1089 →Other connections
- contrasts with1089
why?
Strength 0.50, confidence "high".
Geography
196 is one of the figures commonly given for the number of countries in the world, usually as the 193 United Nations member states plus the Holy See, Palestine and Taiwan. Other defensible counts are 193, 195 and 197, depending on how observer states, Kosovo, Western Sahara and the Cook Islands are treated. No authority publishes a definitive number because recognition is not unanimous, so any count is a statement about which criteria were used rather than a measurement.
DisputedGeography
Mathematics
Reverse a number's digits and add; repeat. Nearly everything reaches a palindrome in a few steps. 196 has been pushed past a billion digits without one, and nobody has proved it never will. The problem needs no background to understand and remains unsolved.
DocumentedMathematics196 = 14², which makes it a slightly awkward candidate for its famous open problem: it is a perfectly ordinary square that happens to sit at the start of an unsolved question about digit reversal. The Lychrel property, if 196 has it, is a fact about how the number is written in base 10 and would not survive translation into another base — which is the general reason digit problems are hard to connect to anything deeper.
DocumentedMathematics
Common questions
Why is 196 special?
It is the smallest number suspected never to produce a palindrome by reverse-and-add. Reverse the digits, add, repeat: almost everything reaches a palindrome within a few steps. 196 has been carried past a billion digits without one, and nobody has proved it never will. The problem needs no background to state and remains open — but note the property is about how the number is written in base 10, not about the quantity.
Is 196 a prime number?
No, 196 is not prime.
What are the factors of 196?
The factors of 196 are 1, 2, 4, 7, 14, 28, 49, 98, 196.
What is 196 in Roman numerals?
196 in Roman numerals is CXCVI. XC is subtractive: ten before a hundred — a hundred minus ten. Written additively it would be CLXXXXVI, which Roman inscriptions used freely — the strict subtractive form is a later convention.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 3 reviewer-confirmed records, sourced and reviewed before publication.
Last reviewed: 15 July 2026