15220
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 32004
- Proper Divisor Sum (Aliquot Sum)
- 16784
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6080
- Möbius Function
- 0
- Radical
- 7610
- 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
- 32
- 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
- Number of paraffins.at n=38A005997
- a(n) = n*(19*n + 1)/2.at n=40A022277
- Number of partitions of n into parts not of the form 23k, 23k+2 or 23k-2. Also number of partitions with 1 part of size 1 and differences between parts at distance 10 are greater than 1.at n=41A035990
- a(n) = smallest number > a(n-1) such that a(1)*a(2)*...*a(n) + 1 and a(1)*a(2)*...*a(n) - 1 are primes.at n=35A051956
- a(n) = n*(2*n^2 - 2*n + 1).at n=20A059722
- Structured truncated icosahedral numbers.at n=9A100154
- Nonnegative values x of solutions (x, y) to the Diophantine equation x^2+(x+761)^2 = y^2.at n=6A122694
- a(n) = ceiling(n/2)*ceiling(n^2/2).at n=39A131474
- Number of subsets of {1, 2, ..., n} containing n and having <=9 pairwise coprime elements.at n=28A186993
- Number of (n+1) X (2+1) 0..2 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally and vertically.at n=4A253450
- Number of (n+1) X (5+1) 0..2 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally and vertically.at n=1A253453
- T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with every 2X2 subblock diagonal minus antidiagonal sum nondecreasing horizontally and vertically.at n=16A253456
- T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with every 2X2 subblock diagonal minus antidiagonal sum nondecreasing horizontally and vertically.at n=19A253456
- Expansion of 1/(Sum_{i>=0} q^(2*i*(i+1))/Product_{j=0..i} (1 - q^(2*j+1))^2).at n=44A294599
- Number of strict compositions of n that are neither increasing nor decreasing.at n=27A333149
- Numbers k such that 3^k + 2*k is prime.at n=16A363797