1219
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 1296
- Proper Divisor Sum (Aliquot Sum)
- 77
- 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
- 1144
- Möbius Function
- 1
- Radical
- 1219
- 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
- 132
- 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
- no
- Odd
- yes
Appears in sequences
- Number of n-gons with n vertices.at n=6A000940
- a(n) = a(n-1) + a(n-2) + 1, with a(0) = a(1) = 1.at n=14A001595
- Number of partitions of n into Fibonacci parts (with a single type of 1).at n=38A003107
- Numbers that are the sum of 9 positive 5th powers.at n=47A003354
- Numbers that are the sum of 10 positive 5th powers.at n=51A003355
- Erroneous version of A000940.at n=6A004577
- a(n) = floor(n*phi^7), where phi is the golden ratio, A001622.at n=42A004922
- a(n) = round(n*phi^7), where phi is the golden ratio, A001622.at n=42A004942
- Centered triangular numbers: a(n) = 3*n*(n-1)/2 + 1.at n=28A005448
- Smith (or joke) numbers: composite numbers k such that sum of digits of k = sum of digits of prime factors of k (counted with multiplicity).at n=52A006753
- 7th-order maximal independent sets in path graph.at n=46A007381
- Number of non-Abelian metacyclic groups of order p^n (p odd).at n=40A007983
- Coordination sequence T1 for Zeolite Code ATT.at n=25A008041
- Composite but smallest prime factor >= 17.at n=38A008367
- Expansion of (1 + 2*x^2 + x^3)/((1 - x)^2*(1 - x^3)).at n=42A008822
- Coordination sequence T2 for Zeolite Code RTH.at n=24A009894
- a(n) = prime(n)*(prime(n-1)-1)/2.at n=13A014302
- Number of ordered triples of integers from [ 2,n ] with no global factor.at n=19A015633
- Let m=n+1; a(n) is the least positive integer s, not a multiple of m, such that if 1<=d<=m and (d,m)=1, then d divides one of the numbers s-m, s-2m, ..., s-m[ s/m ].at n=47A018205
- Numbers whose sum of divisors is a fourth power.at n=12A019422