1725
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 2976
- Proper Divisor Sum (Aliquot Sum)
- 1251
- 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
- 880
- Möbius Function
- 0
- Radical
- 345
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 3
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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 42
- Smith Number
- no
- Vampire 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
- no
- Odd
- yes
Appears in sequences
- Representation degeneracies for boson strings.at n=32A005290
- Coordination sequence T5 for Zeolite Code -CLO.at n=37A009854
- a(n) = floor( n*(n-1)*(n-2)/8 ).at n=25A011890
- Odd numbers k such that d(k) does not divide phi(k).at n=44A015734
- Pseudoprimes to base 68.at n=30A020196
- a(n) = 12^n - n.at n=3A024141
- Number of partitions of n into distinct parts >= 2.at n=49A025147
- Numbers that are the sum of 3 nonzero squares in exactly 10 ways.at n=42A025330
- Numbers that are the sum of 3 distinct nonzero squares in exactly 10 ways.at n=42A025348
- a(n) = Sum{T(n,k-1), k = 1,2,...,n}.at n=7A025578
- a(n) = (d(n)-r(n))/2, where d = A026043 and r is the periodic sequence with fundamental period (1,1,0,0).at n=18A026044
- dot_product(n,n-1,...2,1)*(6,7,...,n,1,2,3,4,5).at n=12A026063
- a(n) = sum of the numbers between the two n's in A026280.at n=37A026283
- a(n) = n^2 + n + 3.at n=41A027688
- a(n) = a(n-1) + a(n-2) + n, a(0) = a(1) = 1.at n=13A030119
- Concatenation of n and n + 8 or {n,n+8}.at n=16A032613
- Decimal part of a(n)^(1/7) starts with n so that a(n) < a(n+1).at n=9A034072
- Upper of pair of consecutive happy numbers.at n=32A035503
- a(n) = A036800(n)/2.at n=6A036826
- Numbers k such that 2 and 5 occur juxtaposed in the base-10 representation of k but not of k-1.at n=34A043235