1658
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 2490
- Proper Divisor Sum (Aliquot Sum)
- 832
- 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
- 828
- Möbius Function
- 1
- Radical
- 1658
- 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
- 91
- 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
- yes
- Odd
- no
Appears in sequences
- Numbers k such that phi(2k-1) < phi(2k), where phi is Euler's totient function A000010.at n=23A001836
- Solid partitions of n which are restricted to two planes.at n=10A002835
- Number of points on surface of truncated cube: a(n) = 46*n^2 + 2 for n > 0.at n=6A005911
- Numbers not of form p + 2^x + 2^y.at n=36A006286
- Number of factors in the infinite word formed by the Kolakoski sequence A000002.at n=44A007782
- Coordination sequence T3 for Zeolite Code LAU.at n=29A008126
- Coordination sequence T1 for Zeolite Code VNI.at n=25A009907
- Molien series of 4-dimensional representation of u.g.g.r. #8.at n=15A013978
- Numbers k such that the continued fraction for sqrt(k) has period 11.at n=14A020350
- Positive numbers k such that k and 3*k are anagrams in base 9 (written in base 9).at n=18A023080
- Conjecturally, number of infinitely-recurring prime patterns on n consecutive integers.at n=24A023192
- Numbers that are the sum of 3 nonzero squares in exactly 10 ways.at n=37A025330
- Numbers that are the sum of 3 distinct nonzero squares in exactly 10 ways.at n=39A025348
- Index of 10^n within the sequence of the numbers of the form 7^i*10^j.at n=52A025745
- a(n) = position of the n-th n in A026409.at n=37A026412
- Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted then there are a pair of central terms both equal to 4.at n=12A031417
- Numbers that, when expressed in base 3 and then interpreted in base 10, yield a multiple of the original number.at n=21A032537
- Expansion of Product_{d | 42} theta_3(q^d).at n=54A033754
- Decimal part of a(n)^(1/6) starts with n so that a(n)<a(n+1).at n=44A034071
- Dirichlet convolution of primes (with 1) with themselves.at n=53A034759