16426
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 25344
- Proper Divisor Sum (Aliquot Sum)
- 8918
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7980
- Möbius Function
- -1
- Radical
- 16426
- 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
- 40
- 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 k | 7^k + 7.at n=26A015893
- Numbers whose base-4 representation contains exactly four 0's and three 2's.at n=15A045060
- T(n,2), array T as in A054126.at n=10A054128
- a(n) = T(n, n-5), array T as in A055818.at n=12A055822
- a(n) = 2^n + 3*n.at n=13A086653
- Same triangle as A106243, but with rows read in boustrophedon manner, i.e., in the order in which they were created.at n=38A106242
- Triangle read by rows from left to right. However, triangle is constructed in the boustrophedon way, reading alternately right to left and left to right. Top entry is 1. In all later rows, initial entry is 0, other entries are sum of previous entry in that row plus sum of two entries above it in previous row.at n=42A106243
- Numbers n with property that for each single digit d of n, we can also see the decimal expansion of 2^d as a substring of n. Also n may not contain any zero digits.at n=9A135016
- Years >= 1801 in which Christmas falls in Sukkot.at n=12A222419
- Number of subsets of {1..n} whose elements have the same smallest prime factor.at n=29A339510
- a(n) = ((p-1)^n + (p+1)^n) mod p^2, where p is the n-th prime.at n=42A379544