1651
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 1792
- Proper Divisor Sum (Aliquot Sum)
- 141
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 1512
- Möbius Function
- 1
- Radical
- 1651
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 135
- 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
- Number of partitions into non-integral powers.at n=9A000263
- Heptagonal numbers (or 7-gonal numbers): n*(5*n-3)/2.at n=26A000566
- Number of partitions of floor(5n/2) into n nonnegative integers each no more than 5.at n=21A001975
- Numbers k such that 33*2^k - 1 is prime.at n=25A002240
- Numbers that are the sum of 6 positive 6th powers.at n=16A003362
- Coefficient of x^4 in expansion of (1+x+x^2)^n.at n=11A005712
- Coordination sequence T2 for Moganite, also for BGB1.at n=26A008259
- Coordination sequence T1 for Zeolite Code GIS.at n=30A008266
- a(n) = n*(n-1) + (n-2)*(n-3) + ... + 1*0 + 1 for n odd; otherwise, a(n) = n*(n-1) + (n-2)*(n-3) + ... + 2*1.at n=20A014112
- Odd heptagonal numbers (A000566).at n=13A014637
- Generalized Fibonacci numbers: a(n) = a(n-1) + 10*a(n-2).at n=6A015446
- Expansion of 1/(1 - x^5 - x^6).at n=73A017837
- Numbers k such that the continued fraction for sqrt(k) has period 36.at n=11A020375
- Index of 5^n within sequence of numbers of form 2^i * 5^j.at n=37A022334
- a(n) = a(n-1) + a(n-2) + 1, with a(0)=3, a(1)=8.at n=12A022407
- a(n) = least m such that if r and s in {1/2, 1/5, 1/8, ..., 1/(3n-1)} satisfy r < s, then r < k/m < (k+1)/m < s for some integer k.at n=18A024837
- a(n) = least m such that if r and s in {1/1, 1/3, 1/5, ..., 1/(2n-1)} satisfy r < s, then r < k/m < (k+4)/m < s for some integer k.at n=13A024847
- a(n) = sum of the numbers between the two n's in A026354.at n=37A026357
- Sums of six consecutive squares: a(n) = n^2 + (n+1)^2 + (n+2)^2 + (n+3)^2 + (n+4)^2 + (n+5)^2.at n=14A027865
- Odd elements in 3-Pascal triangle A028262 (by row) that are not 1.at n=50A028265