15707
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 15960
- Proper Divisor Sum (Aliquot Sum)
- 253
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 15456
- Möbius Function
- 1
- Radical
- 15707
- 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
- 84
- 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
- Coordination sequence for MgNi2, Position Ni3.at n=31A009934
- Number of ternary rooted trees with n nodes and height at most 8.at n=14A036376
- n-th 6k+1 prime times n-th 6k-1 prime.at n=14A048629
- Smallest k not a palindrome and not divisible by 10 such that k and R(k) (A004086) both are divisible by the n-th prime.at n=33A075605
- Numbers n such that n and its reversal are distinct brilliant numbers (A078972).at n=21A097435
- Triangle read by rows: T(n,k) is the number of Motzkin paths of length n and having k peaks at odd height.at n=49A097891
- Both n and the reverse of n are brilliant numbers (A078972).at n=35A115655
- First string of 43 consecutive composite numbers.at n=23A177949
- Number of 0..n arrays x(0..5) of 6 elements with zero 4th differences.at n=23A200084
- Palindromic in bases 7 and 29.at n=21A249158
- Sequence of pairwise relatively prime numbers of class P_8 (see comment in A275246).at n=16A275253
- Largest integer that cannot be represented as x1^2 + ... + xk^2, where k >= 1, n <= x1 < ... < xk, and 1/x1 + ... + 1/xk = 1.at n=5A297896
- Decimal expansion of Pi/2 truncated to n places.at n=4A300077
- a(n) = n^2 + 2329*n + 1697.at n=6A301985
- a(n) = 1^2 + 3^4 + 5^6 + 7^8 + 9^10 + 11^12 + 13^14 + ... + (up to n).at n=5A318868
- a(n) is the least number k for which A330437(k) = n.at n=27A330704
- Triangular array read by rows. T(n,k) is the number of simple unlabeled graphs with n vertices whose components belong to exactly k distinct isomorphism classes.at n=27A331123
- Atomic number corresponding to the element that is the first of the two middle elements in the n-th row of the periodic table of elements.at n=43A349723
- Smallest semiprime p1*p2 such that p2 mod p1 = n and no prime is used more than once in the sequence.at n=25A386256