724
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 1274
- Proper Divisor Sum (Aliquot Sum)
- 550
- 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
- 360
- Möbius Function
- 0
- Radical
- 362
- Omega Function (Ω)
- 3
- 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
- 20
- Smith Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- yes
- Odd
- no
Names
- German
- siebenhundertvierundzwanzig· ordinal: siebenhundertvierundzwanzigste
- English
- seven hundred twenty-four· ordinal: seven hundred twenty-fourth
- Spanish
- setecientos veinticuatro· ordinal: 724º
- French
- sept cent vingt-quatre· ordinal: sept cent vingt-quatrième
- Italian
- settecentoventiquattro· ordinal: 724º
- Latin
- septingenti viginti quattuor· ordinal: 724.
- Portuguese
- setecentos e vinte e quatro· ordinal: 724º
Appears in sequences
- Number of ways of placing n nonattacking queens on an n X n board.at n=10A000170
- Number of partitions of n, with three kinds of 1,2 and 3 and two kinds of 4,5,6,....at n=8A000715
- Numbers n such that the sum of the squares of n consecutive positive odd numbers x^2 + (x+2)^2 + ... + (x+2n-2)^2 = k^2 for some integer k. The least values of x and k for each n are in A056131 and A056132, respectively.at n=45A001033
- Primes multiplied by 4.at n=41A001749
- The square sieve.at n=47A002960
- Almost certainly an erroneous version of A129427.at n=5A003175
- Expansion of 1/((1-x)*(1-2*x)*(1-x-2*x^3)).at n=7A003230
- Numbers that are the sum of 5 positive 4th powers.at n=47A003339
- a(n) = 4*a(n-1) - a(n-2) with a(0) = 2, a(1) = 4.at n=5A003500
- Number of points on surface of tetrahedron; coordination sequence for sodalite net (equals 2*n^2+2 for n > 0).at n=19A005893
- Sum of fourth powers of Fibonacci numbers.at n=4A005969
- Coordination sequence T1 for Zeolite Code ACO, ASV, EDI, and THO.at n=19A008084
- Coordination sequence T2 for Zeolite Code EDI.at n=19A008085
- Coordination sequence T1 for Zeolite Code LEV.at n=20A008127
- Coordination sequence T11 for Zeolite Code MFI.at n=17A008163
- Coordination sequence for diamond.at n=17A008253
- Expansion of cos(log(1 + sin(x))).at n=8A009019
- Coordination sequence for CaF2(2), F position.at n=17A009925
- List of totally balanced sequences of 2n binary digits written in base 10. Binary expansion of each term contains n 0's and n 1's and reading from left to right (the most significant to the least significant bit), the number of 0's never exceeds the number of 1's.at n=31A014486
- a(n) = Sum_{i=1..n} phi(i) * (ceiling(n/i) - floor(n/i)).at n=49A015613