729
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 7
- Divisor Sum
- 1093
- Proper Divisor Sum (Aliquot Sum)
- 364
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 486
- Möbius Function
- 0
- Radical
- 3
- Omega Function (Ω)
- 6
- Little Omega Function (ω)
- 1
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- yes
- Perfect Cube
- yes
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 33
- Smith Number
- yes
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- yes
- Achilles Number
- no
- Perfect Power
- yes
- Smooth Number
- yes
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Names
- German
- siebenhundertneunundzwanzig· ordinal: siebenhundertneunundzwanzigste
- English
- seven hundred twenty-nine· ordinal: seven hundred twenty-ninth
- Spanish
- setecientos veintinueve· ordinal: 729º
- French
- sept cent vingt-neuf· ordinal: sept cent vingt-neufième
- Italian
- settecentoventinove· ordinal: 729º
- Latin
- septingenti viginti novem· ordinal: 729.
- Portuguese
- setecentos e vinte e nove· ordinal: 729º
Appears in sequences
- Powers of 3: a(n) = 3^n.at n=6A000244
- n followed by n^2.at n=53A000463
- Squares that are not the sum of 2 nonzero squares.at n=18A000548
- The cubes: a(n) = n^3.at n=9A000578
- Expansion of bracket function.at n=12A000748
- a(n) = max{(n - i)*a(i) : i < n}; a(0) = 1.at n=18A000792
- Sixth powers: a(n) = n^6.at n=3A001014
- Powers of 9: a(n) = 9^n.at n=3A001019
- Numbers that are the sum of 3 nonnegative cubes in more than 1 way.at n=3A001239
- Numbers that are the sum of 4 cubes in more than 1 way.at n=41A001245
- Triangle of values of 2-d recurrence.at n=57A001404
- Perfect powers: m^k where m > 0 and k >= 2.at n=35A001597
- Powerful numbers, definition (1): if a prime p divides n then p^2 must also divide n (also called squareful, square full, square-full or 2-powerful numbers).at n=44A001694
- Expansion of 1/((1-x^2)*(1-x^4)^2*(1-x^6)*(1-x^8)*(1-x^10)) (even powers only).at n=21A001994
- Quarter-squares: a(n) = floor(n/2)*ceiling(n/2). Equivalently, a(n) = floor(n^2/4).at n=54A002620
- Squares and cubes.at n=33A002760
- Numbers that are the sum of 3 positive 5th powers.at n=9A003348
- 3-smooth numbers: numbers of the form 2^i*3^j with i, j >= 0.at n=36A003586
- Numbers of the form 3^i*5^j with i, j >= 0.at n=18A003593
- Numbers of the form 3^i*7^j with i, j >= 0.at n=15A003594