10278
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
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 22308
- Proper Divisor Sum (Aliquot Sum)
- 12030
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3420
- Möbius Function
- 0
- Radical
- 3426
- 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
- 55
- 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
- a(n) = Sum{T(k,k-1)}, k = 1,2,...,n, where T is the array defined in A026082.at n=10A026095
- Self-convolution of array T given by A026615.at n=7A026956
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 100.at n=23A031598
- Numbers with exactly five distinct base-10 digits.at n=28A031987
- a(n) is the number of unlabeled forests of rooted trees with n nodes such that no two trees are identical.at n=12A052827
- Numbers k such that k^2 contains exactly 9 different digits.at n=4A054037
- Number of partitions of n in which the number of parts divides n.at n=41A067538
- Numbers k such that (k / sum of digits of k) and (k+1 / sum of digits of k+1) are both prime.at n=13A085775
- a(n) = smallest k such that the Reverse and Add! trajectory of A063048(n) joins the trajectory of k.at n=14A089493
- The sums of pairs of adjacent terms are the odd palindromic primes in ascending order.at n=24A181882
- G.f.: exp( Sum_{n>=1} A051064(n)*3^A051064(n)*x^n/n ) where A051064(n) equals the 3-adic valuation of 3n.at n=18A183038
- Number of nondecreasing arrangements of n numbers in -6..6 with sum zero and sum of squares less than n*42/3.at n=9A183932
- Numbers n such that n contains exactly 5 digits, all distinct, and n^2 contains exactly 9 distinct digits.at n=0A204691
- G.f.: exp( Sum_{n>=1} A068963(n)*x^n/n ) where A068963(n) = Sum_{d|n} phi(d^3).at n=12A226106
- a(n) = Sum_{i=0..n} digsum_3(i)^4, where digsum_3(i) = A053735(i).at n=44A231505
- Number of Dyck paths of semilength n such that both consecutive patterns of Dyck paths of semilength 2 occur at least once.at n=10A243965
- Numbers x such that it is possible to find a value k for which Sum_{j=1..x} (x mod j) = Sum_{j=1..k} j.at n=16A244409
- Expansion of Product_{k>=1} ((1 + x^k) * (1 + 2*x^k)).at n=20A266819
- Numbers n such that Bernoulli number B_{n} has denominator 798.at n=42A272138
- p-INVERT of the positive integers, where p(S) = 1 - S - S^2 - S^3 - S^4.at n=7A291030