721

domain: N

Properties

Digital Properties

Digit Count
3
Digit Sum
10
Digital Root
1
Palindromic Number
no
Repdigit
no
Automorphic
no
Kaprekar Number
no
Multiplicative Persistence
2

Divisibility

Divisor Count
4
Divisor Sum
832
Proper Divisor Sum (Aliquot Sum)
111
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
612
Möbius Function
1
Radical
721
Omega Function (Ω)
2
Little Omega Function (ω)
2

Special

Factorial
no
Catalan Number
no
Bell Number
no
Motzkin Number
no
Primorial
no

Figurate Numbers

Fibonacci Number
no
Triangular Number
no
Perfect Square
no
Perfect Cube
no
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
46
Smith Number
no

Primality

Prime
no
Composite Number
yes
Semiprime
yes
Squarefree Number
yes
Prime Power
no
Prime Factorization
no
Twin Prime
no
Mersenne Prime
no
Sophie Germain Prime
no
Safe Prime
no
Powerful Number
no
Achilles Number
no
Perfect Power
no
Smooth Number
no
Carmichael Number
no

Classification

Even
no
Odd
yes

Names

German
siebenhunderteinundzwanzig· ordinal: siebenhunderteinundzwanzigste
English
seven hundred twenty-one· ordinal: seven hundred twenty-first
Spanish
setecientos veintiuno· ordinal: 721º
French
sept cent vingt et un· ordinal: sept cent vingt et unième
Italian
settecentoventuno· ordinal: 721º
Latin
septingenti viginti unus· ordinal: 721.
Portuguese
setecentos e vinte e um· ordinal: 721º

Appears in sequences