12903
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 20736
- Proper Divisor Sum (Aliquot Sum)
- 7833
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7040
- Möbius Function
- 1
- Radical
- 12903
- Omega Function (Ω)
- 4
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 125
- 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
- no
- Odd
- yes
Appears in sequences
- a(n) is the solution to the postage stamp problem with 5 denominations and n stamps.at n=19A001210
- Numbers whose sum of divisors is a fourth power.at n=31A019422
- Numbers k such that k and 7*k are anagrams.at n=4A023091
- a(n) = n*(n+1)*(n^2+5*n+18)/24.at n=21A051744
- Number of subsets of {1, ..., n} with no four terms in arithmetic progression.at n=15A066369
- Numbers n such that sopf(phi(n)) = phi(sopf(n)), where sopf(x) = sum of the distinct prime factors of x.at n=40A076531
- 23 times triangular numbers.at n=33A195039
- a(n) = smallest k having at least three prime divisors d such that (d + n) | (k + n).at n=16A202158
- The least k such that the polynomial cyclotomic(k,x) has n different coefficients.at n=19A231611
- Denominator of asymptotic density of Union{H_p: p is odd prime and p <= n-th prime}, where H_p is {K*p*(p-1)/2 : K integer}.at n=8A231809
- Products p*q*r*s of distinct primes for which (p*q*r*s - 1)/2 is prime.at n=27A234498
- Number of partitions p of n such that (maximal multiplicity over the parts of p) = (number of numbers in p having multiplicity > 1).at n=47A241132
- Numbers x whose digits can be permuted to produce a multiple of x.at n=17A245680
- Numbers k such that (17*10^k - 47)/3 is prime.at n=19A286177
- Number of integer partitions of n whose parts are all equal or whose distinct parts are pairwise coprime.at n=47A304712
- a(n) is the least integer k such that sigma(k)/(d(k)*sopf(k)) = n where d=A000005, sigma=A000203 and sopf=A008472.at n=23A328174
- Number of nonnegative solutions to (x_1)^2 + (x_2)^2 + ... + (x_7)^2 <= n.at n=26A341402
- a(n) = Sum_{x_1|n, x_2|n, x_3|n, x_4|n, x_5|n} gcd(x_1,x_2,x_3,x_4,x_5).at n=49A344139
- First occurrence of n in A345079, or -1 if n does not occur in A345079.at n=19A345080
- Sum of numbers in n-th upward diagonal of triangle the sum of {1; 2,3; 4,5,6; 7,8,9,10; ...} and {1; 2,3; 3,4,5; 4,5,6,7; ...}.at n=42A356288