7210
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 14976
- Proper Divisor Sum (Aliquot Sum)
- 7766
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2448
- Möbius Function
- 1
- Radical
- 7210
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 57
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- yes
- Odd
- no
Appears in sequences
- Number of n-step self-avoiding walks on 5-d cubic lattice.at n=4A010576
- High temperature series for spin-1/2 Ising magnetic susceptibility on 5D simple cubic lattice.at n=4A010579
- Expansion of 1/(1-x^10-x^11-x^12-x^13-x^14-x^15-x^16-x^17).at n=72A017893
- a(n) = s(1)*s(n) + s(2)*s(n-1) + ... + s(k)*s(n+1-k), where k = floor((n+1)/2), s = (natural numbers >= 3).at n=38A024312
- Number of partitions in parts not of the form 7k, 7k+1 or 7k-1. Also number of partitions with no part of size 1 and differences between parts at distance 2 are greater than 1.at n=54A035937
- Matrix 5th power of Stirling2 triangle A008277.at n=33A039813
- Base-9 palindromes that start with 1.at n=28A043028
- 21-gonal numbers: a(n) = n*(19n - 17)/2.at n=28A051873
- Harshad numbers which terminate in their digital sum.at n=39A070938
- Triangle, read by rows, of trinomial coefficients arranged so that there are n+1 terms in row n by setting T(n,k) equal to the coefficient of z^k in (1 + 3*z + z^2)^(n-[k/2]), for n>=k>=0, where [k/2] is the integer floor of k/2.at n=59A099512
- Riordan array (1/sqrt(1-6x+5x^2),(1-3x-sqrt(1-6x+5x^2))/(2x)).at n=40A110165
- Numbers k such that 6*p(k)*p(k+1)*p(k+2)*p(k+3)*p(k+4)*p(k+5)-1 and 6*p(k)*p(k+1)*p(k+2)*p(k+3)*p(k+4)*p(k+5)+1 are twin primes with p(h) = h-th prime.at n=10A129311
- Numbers which are the sum of three cubes of distinct primes.at n=35A138854
- Twice octagonal numbers: 2*n*(3*n-2).at n=35A139267
- Numbers A141427(k) such that the three numbers A141427(k) -/+ 3 and A141427(k) + 1 are all prime.at n=48A144206
- Triangle T(n,k), n >= 0, 0 <= k <= n, read by rows: T(n,k) is the number of forests of trees on n or fewer nodes using a subset of labels 1..n and k edges.at n=31A144258
- Numbers n with property that the sum of the digits of n is substring of n and of n^2.at n=41A162015
- Numbers k such that the sum of the decimal digits of k is a substring of k, of k^2 and of k^3.at n=23A162017
- Number of reduced words of length n in the Weyl group D_7.at n=30A162210
- Number of reduced words of length n in the Weyl group D_7.at n=12A162210