7906
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 12240
- Proper Divisor Sum (Aliquot Sum)
- 4334
- 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
- 3828
- Möbius Function
- -1
- Radical
- 7906
- Omega Function (Ω)
- 3
- 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
- 52
- 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
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite DAC = Dachiardite Na5[Al5Si19O48].12H2O starting with a T1 atom.at n=12A019102
- Convolution of Lucas numbers and A014306.at n=17A023624
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 88.at n=12A031586
- Number of partitions of n into parts not of the form 15k, 15k+6 or 15k-6. Also number of partitions with at most 5 parts of size 1 and differences between parts at distance 6 are greater than 1.at n=34A035960
- Base-7 palindromes that start with 3.at n=30A043017
- Numbers n such that 167*2^n-1 is prime.at n=22A050835
- Lengths of intervals between special points in Recamán's sequence A005132.at n=15A065053
- Centered 17-gonal numbers: (17*n^2 - 17*n + 2)/2.at n=30A069130
- Number of symmetric real invertible (0,1) n X n matrices with (-1,0,1) inverses.at n=4A080636
- Logarithm of triangular matrix A102220, which equals [2*I - A008459]^(-1).at n=15A102222
- Column 0 of triangular matrix A102222, which equals -log[2*I - A008459].at n=5A102223
- Triangle, read by rows, given by [0,1,1,1,1,1,1,1,...] DELTA [1,0,1,0,2,0,3,0,4,0,5,0,6,0,...] where DELTA is the operator defined in A084938.at n=47A173050
- Number of 5X2 integer matrices with each row summing to zero, row elements in nondecreasing order, rows in lexicographically nondecreasing order, and the sum of squares of the elements <= 2*n^2 (number of collections of 5 zero-sum 2-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations).at n=18A192705
- a(n) = 8*n^2 + 7*n + 1.at n=31A194268
- Numbers k such that k, k+1, k+2, and k+3 are not divisible by any of their nonzero digits.at n=40A244358
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 190", based on the 5-celled von Neumann neighborhood.at n=26A270683
- Numbers whose carryless sum of divisors is zero.at n=6A323414
- Heinz number of the multiset of differences between consecutive divisors of n.at n=37A328023
- a(n) = Sum_{k=1..n} phi(k) * (floor(n/k)^3 - floor((n-1)/k)^3).at n=45A344599
- Numbers that are the sum of six fourth powers in three or more ways.at n=33A345560