7231
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 8272
- Proper Divisor Sum (Aliquot Sum)
- 1041
- 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
- 6192
- Möbius Function
- 1
- Radical
- 7231
- 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
- 70
- Smith Number
- no
- Vampire 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
Appears in sequences
- Number of paraffins.at n=30A005998
- a(n) = floor( n*(n-1)*(n-2)/23 ).at n=56A011905
- Fibonacci sequence beginning 3, 10.at n=15A022122
- Numbers k such that Fib(k) == -13 (mod k).at n=28A023167
- Lucky numbers with size of gaps equal to 16 (upper terms).at n=21A031899
- Numbers whose set of base-15 digits is {1,2}.at n=28A032935
- Multiplicity of highest weight (or singular) vectors associated with character chi_49 of Monster module.at n=39A034437
- a(i) is a square mod a(j), i <> j.at n=18A034903
- Numbers whose base-4 representation contains exactly two 0's and four 3's.at n=15A045075
- Number of 2 X 2 singular integer matrices with elements from {0,...,n}.at n=30A059306
- Numbers k such that (32*10^(k-1) - 23)/9 is a plateau prime.at n=8A082707
- Numbers k such that each of k through k+4 are divisible by exactly two primes.at n=45A088986
- Start with 1 and repeatedly reverse the digits and add 42 to get the next term.at n=20A118075
- Start with 1 and repeatedly reverse the digits and add 15 to get the next term.at n=47A118532
- Central moment sequence of tr(A^4) in USp(6).at n=8A138545
- a(n) = 29 + 73*n + 37*n^2.at n=13A145980
- Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 11011-01110 pattern in any orientation.at n=11A147226
- Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 11011-01110 pattern in any orientation.at n=25A147228
- Number of primes of the form x^8 + 1 less than 10^n.at n=43A214454
- Triangle read by rows, T(n,k) for 0<=k<=n, generalizing A098742.at n=51A216916