15642
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 37440
- Proper Divisor Sum (Aliquot Sum)
- 21798
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4680
- Möbius Function
- 0
- Radical
- 5214
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 4
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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 102
- 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
- Expansion of Product_{m>=1} (1-m*q^m)^-11.at n=5A022735
- Obtainable by applying +, * and exponentiation to its own digits.at n=22A046469
- Numbers k such that 3*2^k + 7 is prime.at n=32A059746
- Integers y such that for some integer x we have uphi(x) = uphi(y) = x-y, where uphi(n) = A047994(n) is the unitary totient function: If n = Product p_i^e_i, uphi(n) = Product (p_i^e_i - 1).at n=11A067741
- "Orderly" Friedman numbers (or "good" or "nice" Friedman numbers): Friedman numbers (A036057) where the construction digits are used in the proper order.at n=32A080035
- a(n) = n^3 + 17.at n=25A084379
- Scaled array A078740 ((3,2)-Stirling2).at n=46A090452
- Third to last entries in rows of array A090452 (scaled (3,2)-Stirling2).at n=5A091031
- Total number of smallest parts in all compositions of n.at n=12A097941
- Numbers n such that sigma(n) = 8*phi(n).at n=10A104901
- Sum of squares of first n tribonacci numbers (A000213).at n=9A107240
- Numbers m with odd length such that m = d_1+(d_2^d_3)+ ...+(d_(k-1)^d_k) where d_1 d_2 ... d_k is the decimal expansion of m.at n=11A112014
- Numbers which converge to 2592 under repeated application of the powertrain map of A133500.at n=12A135384
- Integers N such that by inserting + or - or * or / or ^ between each of their digits, without any grouping parentheses, you can get N (the ambiguous a^b^c is avoided).at n=8A156954
- Integers n such that by inserting between their digits + or - or * or / or ^ or nothing (i.e., concatenate two digits) you recover n back in a nontrivial way.at n=10A157198
- Position where 10^n-1 occurs in the Kaprekar sequence A006886.at n=33A193992
- Irregular array T(n,k) of the numbers of non-extendable (complete) non-self-adjacent simple paths ending at each of a minimal subset of nodes within a square lattice bounded by rectangles with nodal dimensions n and 5, n >= 2.at n=51A214359
- Irregular array T(n,k) of the numbers of non-extendable (complete) non-self-adjacent simple paths ending at each of a minimal subset of nodes within a square lattice bounded by rectangles with nodal dimensions n and 8, n >= 2.at n=22A214375
- Number of unrooted binary leaf-multi-labeled trees with n leaves on the label set [3], with each label used at least once.at n=8A220830
- Numbers n such that sigma(Rev(phi(n))) = phi(Rev(sigma(n))), where sigma is the sum of divisors and phi the Euler totient function.at n=6A252255