7876
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 28
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 15120
- Proper Divisor Sum (Aliquot Sum)
- 7244
- 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
- 3560
- Möbius Function
- 0
- Radical
- 3938
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 26
- 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
- yes
- Odd
- no
Appears in sequences
- a(n) = Sum_{k=0..n} f(k)*f(n-k) where f(k) = A002124(k).at n=33A002125
- Number of paraffins.at n=25A006001
- Numbers k such that the continued fraction for sqrt(k) has period 70.at n=23A020409
- a(n) = Sum_{k=0..n} T(n,k)*T(n,2n-k), T given by A027960.at n=7A027979
- Second 10-gonal (or decagonal) numbers: n*(4*n+3).at n=44A033954
- Self-convolution of 1 2 3 5 7 11 15 22 30 42 56 77 ... (A000041).at n=15A048574
- Number of partitions of 2n whose Ferrers-Young diagram allows more than one different domino tiling.at n=17A052837
- Start with 0; to get next term reverse digits and add 1 to each digit (9's get replaced by 10's).at n=26A061729
- Dimension of the space of weight n cuspidal newforms for Gamma_1( 89 ).at n=24A063362
- Numbers n for which there are exactly twelve k such that n = k + reverse(k).at n=7A072435
- a(n) = (9*n^2 - 3*n + 2)/2.at n=42A080855
- Members of A000124 which are multiples of 11.at n=22A083511
- Numbers n such that (Pi/sqrt(2))^n is closer to its nearest integer than any value of (Pi/sqrt(2))^k for 1 <= k < n.at n=13A095203
- Numbers n such that 4*10^n + 2*R_n + 5 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=8A102986
- Triangle read by rows: T(n,k) is the coefficient of t^k (k>=0) in the polynomial P[n,t] defined by P[1,t] = P[2,t] = 1, P[3,t] = 1+t, P[n,t] = P[n-1,t] + P^2[n-2,1] for n >= 4.at n=36A103525
- Right-angled numbers with an internal digit as the vertex.at n=42A135602
- Numbers A141427(k) such that the three numbers A141427(k) -/+ 3 and A141427(k) + 1 are all prime.at n=50A144206
- Number of permutations of floor(i*4/3), i=0..n-1, with all sums of two and three adjacent terms respectively unique.at n=7A147925
- Number of permutations of floor(i*4/3), i=0..n-1, with all sums of 2 through 4 adjacent terms respectively unique.at n=7A147934
- Number of permutations of floor(i*4/3), i=0..n-1, with all sums of 2 through 5 adjacent terms respectively unique.at n=7A147943