12390
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
- 32
- Divisor Sum
- 34560
- Proper Divisor Sum (Aliquot Sum)
- 22170
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2784
- Möbius Function
- -1
- Radical
- 12390
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 5
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
- 187
- 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
- yes
- Odd
- no
Appears in sequences
- Matrix 5th power of Stirling2 triangle A008277.at n=42A039813
- Products of exactly 5 distinct primes.at n=33A046387
- Expansion of (1 + 4*x + 14*x^2 + 34*x^3 + 63*x^4 + 80*x^5 + 87*x^6 + 68*x^7 + 42*x^8 + 20*x^9 + 7*x^10) / ((1 - x)*(1 - x^2)^2*(1 - x^3)^2*(1 - x^4)).at n=12A055384
- Numbers k such that 5*10^k + R_k is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=11A056713
- Number of labeled n-node 4-valent graphs containing a loop and a double edge.at n=7A058837
- Sum of squares of digits of n is equal to the largest prime factor of n reversed, where the largest prime factor is not a palindrome.at n=19A074303
- a(n) = 7*n^2 + n.at n=42A092277
- Indices of primes in sequence defined by A(0) = 61, A(n) = 10*A(n-1) + 21 for n > 0.at n=24A101525
- First monotonically increasing sequence such that erasing the first and last digit of each term and concatenating what is left results in the concatenation of all terms of the sequence.at n=39A106004
- Numbers k for which nontrivial positive magic squares of exactly 9 different orders with magic sum k exist. For a definition of nontrivial positive magic squares, see A125005.at n=17A125016
- Number of bits in A127962(n).at n=27A127965
- Records for unitary abundant numbers, i.e., those integers which set a record for having a greater unitary abundance than any of their predecessors.at n=34A129499
- Number of permutations of 1..n with the sequence of sums of 2 adjacent elements having exactly 3 maxima.at n=3A179712
- Second accumulation array, T, of the natural number array A000027, by antidiagonals.at n=85A185507
- Fourth accumulation array of A051340, by antidiagonals.at n=51A185876
- Expansion of 2*x^2 *(4 +7*x +5*x^2 -x^3 -4*x^4 +6*x^6 +4*x^7 -x^8 -2*x^9) / ((1+x)^2 *(1+x+x^2)^2 *(1-x)^4) .at n=41A187062
- Riordan array (1, x*(1-x)/(1-3*x+x^2)).at n=48A188137
- 7 times hexagonal numbers: a(n) = 7*n*(2*n-1).at n=30A195320
- Numbers n such that smallest number not dividing n^2 (A236454) is different from smallest prime not dividing n (A053669).at n=29A235921
- a(n) = (2*n-1)*210; numbers which are 210 times an odd number.at n=29A236432