1236
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 2912
- Proper Divisor Sum (Aliquot Sum)
- 1676
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 408
- Möbius Function
- 0
- Radical
- 618
- 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
- yes
- 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
- 6th power of rooted tree enumerator; number of linear forests of 6 rooted trees.at n=5A000395
- Powers of rooted tree enumerator.at n=5A000529
- a(n) is the number of conjugacy classes in the alternating group A_n.at n=25A000702
- a(1) = 1; thereafter a(n+1) = floor(sqrt(2*a(n)*(a(n)+1))).at n=19A001521
- Prime numbers of measurement.at n=33A002049
- Number of protruded partitions of n with largest part at most 3.at n=11A005404
- Truncated square numbers: 7*n^2 + 4*n + 1.at n=13A005892
- Oscillates under partition transform.at n=35A007213
- Coordination sequence T1 for Zeolite Code LEV.at n=26A008127
- Coordination sequence T1 for Zeolite Code RTE.at n=24A009890
- Expansion of Molien series for automorphism group (2.Weyl(E6)) of E6 lattice.at n=37A014977
- Numbers n such that phi(n) * sigma(n) + 4 is a perfect square.at n=29A015727
- phi(n) + 8 | sigma(n).at n=44A015799
- a(n) is the concatenation of n and 3n.at n=11A019551
- Numbers k such that the continued fraction for sqrt(k) has period 26.at n=25A020365
- a(n) = [ a(n-1)/a(1) ] + [ a(n-3)/a(3) ] + [ a(n-5)/a(5) ] + ..., for n >= 3.at n=19A022860
- Sum of distinct prime divisors of prime(n)*prime(n-1) - 1.at n=22A023521
- Katadromes: digits in base 6 are in strict descending order.at n=51A023788
- [ (4th elementary symmetric function of S(n))/(3rd elementary symmetric function of S(n)) ], where S(n) = {first n+3 positive integers congruent to 1 mod 4}.at n=48A024390
- s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (odd natural numbers), t = A001950 (upper Wythoff sequence).at n=13A024600