7695
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 20
- Divisor Sum
- 14520
- Proper Divisor Sum (Aliquot Sum)
- 6825
- 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
- 3888
- Möbius Function
- 0
- Radical
- 285
- Omega Function (Ω)
- 6
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 145
- Smith Number
- yes
- 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
- Number of n-node animals on f.c.c. lattice.at n=6A007199
- G.f.: 1/((1-6*x)*(1-9*x)*(1-12*x)).at n=3A020724
- Least k>1 such that reverse of first n terms of A006928 repeats beginning at k-th term.at n=44A025509
- Numbers k such that 101*2^k+1 is prime.at n=23A032400
- Odd numbers divisible by exactly 6 primes (counted with multiplicity).at n=23A046319
- Numbers n such that { x +- 2^k : 0 < k < 4 } are primes, where x = 210*n - 105.at n=5A061671
- Numbers k for which phi(prime(k)) is a square.at n=46A062325
- Lesser of two consecutive numbers each divisible by a fourth power.at n=14A068782
- Numbers k such that k = (sum of distinct prime factors of k)*(product of distinct prime factors of k).at n=36A068999
- Numbers k such that tau_3(k) (the number of ordered factorizations of k as k = r*s*t) divides k.at n=33A069147
- a(n) = A061680(n!).at n=39A069785
- a(n) = A061680(n!).at n=40A069785
- Numbers k such that the sum of the digits of k equals the sum of the prime divisors of k.at n=33A070275
- Numbers k such that gcd(k, reverse(k)) = 27 = 3^3, where reverse(x) = A004086(x).at n=21A072016
- Triangle T(n,d) (listed row-wise: T(1,1)=1, T(2,1)=1, T(2,2)=1, T(3,1)=2, T(3,2)=0, T(3,3)=1, ...) giving the number of n-edge general plane trees with root degree d that are fixed by the five-fold application of Catalan Automorphisms A057511/A057512 (Deep rotation of general parenthesizations/plane trees).at n=82A079221
- a(1) = 1; for n > 1: a(n) = smallest number >1 such that product of any two or more successive terms + 1 is prime.at n=7A096100
- Expansion of g.f. Product_{k>=1} 1/(1-x^sigma(k)).at n=46A111865
- Numbers k such that 9*k = A048720(25,k), where A048720 is carryless base-2 multiplication.at n=48A115801
- Integers i such that 9*i = 25 X i, but 17*i is not 49 X i.at n=11A115811
- Numbers k such that 2k+1, 4k+1, 6k+1 and 8k+1 are primes.at n=7A124409