7438
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
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 11160
- Proper Divisor Sum (Aliquot Sum)
- 3722
- 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
- 3718
- Möbius Function
- 1
- Radical
- 7438
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- 44
- Smith Number
- yes
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- a(0) = 1, a(n) = 11*n^2 + 2 for n>0.at n=26A010003
- Numbers k such that the continued fraction for sqrt(k) has period 100.at n=10A020439
- 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 86.at n=2A031584
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 36 ones.at n=36A031804
- Numbers k such that A102489(k) is divisible by k.at n=29A032563
- Turns at which card 1 surfaces in Guy's shuffling problem (A035485).at n=8A035499
- Number of partitions of n such that cn(0,5) = cn(2,5) <= cn(3,5) = cn(4,5) < cn(1,5).at n=57A036847
- Numbers k such that A001414(k) is a square and sets a new record for squares.at n=21A064463
- Numbers k such that p(k), p(k)+6, p(k)+12, p(k)+18 are consecutive primes, where p(k) denotes k-th prime.at n=24A090832
- Numbers n such that if p=prime(n), then p, p+6, p+12, p+18 are consecutive primes with p=6*k+5 for some k, where prime(n) denotes n-th prime.at n=12A090835
- Sum_{k=2..n} min(k,n-k)*phi(k)*(n-k).at n=22A092274
- a(n+1) is the integer part of sqrt(2*a(n)^2).at n=24A102822
- Least positive k such that k * Z^n + 1 is prime, where Z = 10^100+267, the first prime greater than a googol.at n=37A108344
- Expansion of x/((1-x-x^3)*(1-x)^4).at n=14A144898
- Shifted Pascal sequence: p(x,n)=(1 + x)^(n + 1) + If[n < 2, 0, x*((1 - x)^(n + 1)*PolyLog[ -n, x]/x + (1 + x)^(n - 1))/2].at n=58A147532
- Shifted Pascal sequence: p(x,n)=(1 + x)^(n + 1) + If[n < 2, 0, x*((1 - x)^(n + 1)*PolyLog[ -n, x]/x + (1 + x)^(n - 1))/2].at n=62A147532
- a(n) = 2*prime(n)^2 - 4.at n=17A153480
- a(n) is the number of n-tosses having a run of 3 or more heads or a run of 3 or more tails for a fair coin (i.e., probability is a(n)/2^n).at n=12A167821
- Partial sums of A027642.at n=27A173242
- a(n) = -1 + n + 4*n^2.at n=43A182868