1553
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 1554
- Proper Divisor Sum (Aliquot Sum)
- 1
- 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
- 1552
- Möbius Function
- -1
- Radical
- 1553
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- 122
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 245
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of n-node steric rooted ternary trees; number of n carbon alkyl radicals C(n)H(2n+1) taking stereoisomers into account.at n=10A000625
- Number of solutions to a linear inequality.at n=35A002797
- Number of polygons that can be formed from n points on a circle, no two adjacent.at n=8A002816
- Numbers which are the sum of 3 nonzero 4th powers.at n=40A003337
- Sums of distinct nonzero 4th powers.at n=40A003999
- Divisible only by primes congruent to 6 mod 7.at n=44A004624
- Class 4+ primes (for definition see A005105).at n=25A005108
- Number of shapes of height-balanced AVL trees with n nodes.at n=15A006265
- Primes with both 10 and -10 as primitive root.at n=46A007349
- Primes p == 1 (mod 8), p = a^2 + 64*b^2 such that y^2 = x^3 + p*x has rank 2.at n=19A007766
- Coordination sequence T1 for Zeolite Code LOV.at n=26A008134
- Coordination sequence T7 for Zeolite Code MTW.at n=26A008202
- Expansion of tanh(tan(sin(x))).at n=4A009807
- Primes p == 1 mod 8 such that 2 and -2 are both 4th powers (one implies other) mod p.at n=25A014754
- Numbers k such that the continued fraction for sqrt(k) has period 15.at n=11A020354
- Place where n-th 1 occurs in A007336.at n=46A022775
- Primes that remain prime through 2 iterations of function f(x) = 2x + 3.at n=31A023242
- Numbers that are the sum of 3 nonzero squares in exactly 10 ways.at n=31A025330
- Numbers that are the sum of 3 distinct nonzero squares in exactly 9 ways.at n=21A025347
- Irregular triangular array T read by rows: T(0,0) = 1, T(0,1) = T(0,2) = 0; T(1,0) = T(1,1) = T(1,2) = 1, T(1,3) = 0; for n >= 2, T(n,0) = 1, T(n,1) = T(n-1,0) + T(n-1,1), T(n,k) = T(n-1,k-2) + T(n-1,k-1) + T(n-1,k) for k = 2,3,...,n+1 and T(n,n+2) = T(n-1,n) + T(n-1,n+1).at n=69A026323