15122
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 11
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 22686
- Proper Divisor Sum (Aliquot Sum)
- 7564
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7560
- Möbius Function
- 1
- Radical
- 15122
- 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
- 84
- Smith Number
- no
- 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
- Nearest integer to 24*(2^n - 1)/n.at n=12A003138
- a(n) = ceiling(24(2^n-1)/n).at n=12A003177
- Fibonacci numbers written in base 7.at n=19A004690
- Coordination sequence for sigma-CrFe, Position Xf.at n=31A009958
- Number of ways to partition {1,2,...,n} into arithmetic progressions, where in each partition all the progressions have the same common difference and have lengths >= 2.at n=22A072255
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 0, 1), (1, 0, -1), (1, 0, 1), (1, 1, 1)}.at n=7A150958
- Numbers that are the product of two distinct primes and they are partial sum of products of two distinct primes.at n=29A168476
- Places of records of A188550.at n=19A188592
- Numbers n such that 3, 5 and 7 do not divide swing(n) = A056040(n).at n=14A196749
- Simple continued fraction expansion of product {k >= 0} (1 - 2*(N - sqrt(N^2-1))^(4*k+3))/(1 - 2*(N - sqrt(N^2-1))^(4*k+1)) at N = 4.at n=9A221194
- Number of 1's in A132199 preceding the n-th Rowland prime, A137613(n).at n=34A226781
- Number of 1's in A132199 preceding the n-th Rowland prime, A137613(n).at n=35A226781
- Triangle T(n,k) giving the smallest term in "the infinite trunk of factorial beanstalk" (A219666) whose factorial base representation contains n digits (A084558) and the most significant such digit (A099563) is k.at n=23A230428
- Number of (n+2)X(7+2) 0..1 arrays with every 3X3 subblock sum of the two sums of the diagonal and antidiagonal minus the two minimums of the central column and central row nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=32A254906
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 62", based on the 5-celled von Neumann neighborhood.at n=33A270081
- a(n) = Fibonacci(n) represented in bijective base-7 numeration.at n=18A282238
- Numbers n such that there are precisely 2 groups of order n and 3 of order n + 1.at n=14A296025
- Number of compositions (ordered partitions) of n into distinct parts, the least being 4.at n=45A339165
- a(n) is the number of boards in English Peg Solitaire, reached after n moves, for which no more moves are possible.at n=21A350998
- Numbers k such that k, k+1, k+2, k+3 have 2, 3, 4, 5 prime factors respectively, counted with multiplicity.at n=17A363391