10987
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 10988
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10986
- Möbius Function
- -1
- Radical
- 10987
- 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
- 99
- 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
- 1334
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- a(n) = ceiling(10000*log(n)).at n=2A004245
- a(n) = [ a(n-1)/a(1) + a(n-3)/a(3) + a(n-5)/a(5) + ... ], for n >= 3.at n=37A022871
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 64 ones.at n=18A031832
- Prime concatenated analog clock numbers read counterclockwise.at n=7A036343
- Prime concatenated analog clock numbers (clockwise and counterclockwise).at n=11A036344
- Discriminants of imaginary quadratic fields with class number 11 (negated).at n=35A046008
- Smallest prime formed by concatenating n consecutive decreasing numbers, 0 if no such prime exists.at n=3A052078
- Primes whose decimal expansion is a concatenation of two or more consecutive decreasing numbers (no leading zeros allowed).at n=11A052088
- Primes p from A031924 such that A052180(primepi(p)) = 29.at n=8A052236
- Primes which, although they have correct parity, are not in the prime number maze.at n=18A065123
- Primes in which neighboring digits differ at most by 1.at n=45A068148
- Primes whose digits can be arranged in increasing cyclic order - to form a substring of 123456789012345678901234567890...at n=26A068710
- Group the natural numbers such that the n-th group contains n terms and the group sum is the smallest possible prime: (2), (1, 4), (3, 5, 9), (6, 7, 8, 10), (11, 12, 13, 14, 17), (15, 16, 18, 19, 20, 21), ... Sequence gives group sums.at n=27A075345
- Numbers in ascending order formed by using all the digits of the next n numbers.at n=14A081991
- Primes p such that p-2 and p+2 are divisible by a cube.at n=1A089202
- A B3-sequence: a(1) = 1; for n>1, a(n) = smallest number > a(n-1) such that the sums of any three terms are all distinct.at n=19A096772
- a(1)=0, and a(n+1) is the position of first occurrence of a(n) in the decimal expansion of 1/Pi.at n=35A098319
- Numbers k such that N*2^k + 1 is prime where N = 9999999999999999999999988888888888888888887777777777777777766666666666665555555555544444443333322211.at n=18A098467
- Smallest available integer which fits into the repeating pattern 9876543210.at n=46A098756
- Maximum determinant that can be formed from the optimal set of nonnegative 3 X 3 matrix elements <=n, which maximize the number of different determinants given in A099834.at n=21A099815