Properties of the Number 729

Seven Hundred Twenty-Nine

Basics

Value: 728 → 729 → 730

Parity: odd

Prime: No

Previous Prime: 727

Next Prime: 733

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ⁶

Divisors: 1, 3, 9, 27, 81, 243, 729

Polygonal

Triangular: No

Square: Yes

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

4823 Try Today's Challenge

Representations

Binary: 1011011001

Octal: 1331

Duodecimal: 509

Hexadecimal: 2d9

Square: 531441

Square Root: 27

Classification

Fibonacci: No

Bell Number: No

Factorial Number: No

Regular Number: Yes

Perfect Number: No

Special

Kaprekar Constant: No

Munchausen Constant: No

Armstrong Number: No

Kaprekar Number: No

Catalan Number: No

Vampire Number: No

Taxicab Number: No

Super Prime: No

Friedman Number: No

Fermat Number: No

Cullen Number: No

OEIS Sequences

The squares: a(n) = n². A290

The cubes: a(n) = n³. A578

Completely multiplicative with a(prime(k)) = prime(k+1). A3961

Powers of 3: a(n) = 3ⁿ. A244

Perfect powers: m^k where m > 0 and k >= 2. A1597

Powerful numbers, definition (1): if a prime p divides n then p² must also divide n (also called squareful, square full, square-full or 2-powerful numbers). A1694

Quarter-squares: a(n) = floor(n/2)*ceiling(n/2). Equivalently, a(n) = floor(n²/4). A2620

3-smooth numbers: numbers of the form 2ⁱ*3^j with i, j >= 0. A3586

Odd squares: a(n) = (2n+1)². Also centered octagonal numbers. A16754

Product of divisors of n. A7955