13479
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 17976
- Proper Divisor Sum (Aliquot Sum)
- 4497
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8984
- Möbius Function
- 1
- Radical
- 13479
- 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
- 89
- 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
- no
- Odd
- yes
Appears in sequences
- Numbers k where |cos(k)| (or |cosec(k)| or |cot(k)|) decreases monotonically to 0; also numbers k where |tan(k)| (or |sec(k)|, or |sin(k)|) increases.at n=43A004112
- Numbers k such that the continued fraction for sqrt(k) has period 90.at n=29A020429
- a(n) = Sum_{k=0..floor((n-1)/2)} T(n,k) * T(n,k+1), with T given by A008315.at n=8A027302
- Numbers k where cos(k) decreases monotonically to 0.at n=22A046957
- Numbers k where sin(k) increases monotonically to 1 (or cosec(k) decreases).at n=26A046959
- Total sum of prime parts in all partitions of n.at n=22A073118
- Numbers k such that (k-1)*binomial(2k,k) + 1 is prime.at n=49A085793
- Numbers n such that 9*10^n + 5*R_n - 4 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=18A103100
- Numbers n such that p(5n) is prime, where p(n) is the number of partitions of n.at n=33A114166
- a(n) = least k such that the remainder of 30^k divided by k is n.at n=41A128370
- 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, 0, 0), (0, 1, 1), (1, -1, 0), (1, 0, -1)}.at n=9A148924
- Indices j in A000040 such that j is an odd composite and the distinct digits of the prime A000040(j) are in increasing order.at n=38A155775
- Numbers n>0 such that (7*10^(n+2)+666)*10^n+7 is prime.at n=11A186521
- Number of nondecreasing arrangements of 6 nonzero numbers in -(n+4)..(n+4) with sum zero.at n=8A188336
- G.f.: A(x) = Sum_{n>=0} x^n / Product_{k=1..n} (1-x^k)^k.at n=20A206100
- Number of partitions of n such that (number parts having multiplicity 1) is a part or (number of 1s) is a part.at n=36A241510
- Indices of primes in A000219.at n=36A285216
- Numbers n=2*k-1 where Sum_{j=1..k} (-1)^(j+1) * d(2*j-1) achieves a new negative record, with d(n) = number of divisors of n (A000005).at n=19A318738
- Numbers k such that the concatenation k21 is a square.at n=46A321383
- Number of integer partitions of n with reverse-alternating sum >= 0.at n=38A344607