12478
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 19872
- Proper Divisor Sum (Aliquot Sum)
- 7394
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5856
- Möbius Function
- -1
- Radical
- 12478
- 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
- 50
- 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
- Numbers k such that the continued fraction for sqrt(k) has period 76.at n=39A020415
- Numerators of continued fraction convergents to sqrt(308).at n=7A041580
- Numbers k such that (k-1)*binomial(2k,k) + 1 is prime.at n=48A085793
- Concatenating n with n+1 (in base 10) gives a number which is the product of 2 palindromes.at n=13A113942
- a(0) = a(1) = 1; for n >= 2, a(n) = a(n-1) + a(n-2) - (n-1) if that number is positive and not already in the sequence, otherwise a(n) = a(n-1) + a(n-2) + (n-1).at n=22A117822
- a(n) = 2*prime(n)^2 - 4.at n=21A153480
- Number of 12-core partitions of n.at n=51A192061
- Sums involving triangle A096815.at n=10A212422
- G.f. satisfies: A(x) = sqrt(1 + 2*x*A(x)^4 + 3*x^2*A(x)^6).at n=6A222050
- Products of any two not necessarily distinct terms of A237424.at n=42A254143
- Remove in decimal representation of A254143(n) all repeated digits.at n=42A254323
- Consider the figure made up of a row of n adjacent congruent rectangles, with diagonals of all possible rectangles drawn; a(n) is the number of interior vertices where exactly four lines cross.at n=40A336490
- G.f. A(x) satisfies: A(x) = x + x^3 * exp(A(x) - A(x^2)/2 + A(x^3)/3 - A(x^4)/4 + ...).at n=30A346031