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Number Buffet

Number analysis

76

76 is a composite even number that factors as 2^2 × 19.

76 is a composite even number that factors as 2^2 × 19.

CompositeLucasAutomorphic

The number itself

Value
76
Digits
2
Digit sum
13

7 + 6

Digit sum repeated until one digit remains; equals n mod 9 (with 9 for multiples of 9).

Reversed
67

Reverses to 67.

Parity and primality

Parity
Even

Divisible by 2.

Prime
No

Composite — it factors as 2^2 × 19.

2 distinct prime factors, 3 with multiplicity.

Squarefree
No

At least one prime appears squared.

Möbius μ(n)
0

Zero, because a squared prime divides n.

Nearest primes
73 ← → 79

A gap of 6 between them.

Divisors

1, 2, 4, 19, 38, 76

Aliquot sum
64

The proper divisors — everything except n itself.

Classification
Deficient

Its proper divisors fall short by 12.

How many integers from 1 to n share no factor with n.

Sums and additive structure

Sum of two squares
No

A prime congruent to 3 mod 4 divides it an odd number of times, which rules it out.

Sum of three squares
Yes

Legendre's three-square theorem allows it.

Sum of four squares
Yes

Lagrange's four-square theorem: every non-negative integer is, without exception.

Goldbach pair
3 + 73

The smallest pair of primes summing to n. Goldbach’s conjecture says one always exists; it remains unproven.

Shapes and sequences

Lucas number
Yes — index 9

Digit curiosities

Summing the squares of its digits falls into the 4 → 16 → 37 → … → 4 cycle.

Harshad number
No

Not divisible by its digit sum 13.

Its square 5,776 ends in 76.

Collatz trajectory
22 steps to 1

Peaks at 88 along the way.

Written other ways

Binary
1001100
Octal
114
Base 36
24
In words
seventy-six
Scientific notation
7.6 × 10^1

Is 76 a prime number?

Composite — it factors as 2^2 × 19.

Nearby numbers

Analyse any number up to a trillion · All generators

Other numeral systems

Beyond the bases and Roman numerals above, these notations write 76 their own way.

Greek (alphabetic)
ΟΣΤʹ
Babylonian cuneiform
𒐕𒌋𒐚
Tamil
௭௰௬

References

Further reading: Wikipedia · Wikidata

Notations, naming and the links above come from Wikidata, whose structured data is dedicated to the public domain under CC0-1.0. Retrieved 2026-10-07.