Properties of the Number 21147

Twenty-One Thousand One Hundred Forty-Seven

Basics

Value: 21146 → 21147 → 21148

Parity: odd

Prime: No

Previous Prime: 21143

Next Prime: 21149

Digit Sum: 15

Digital Root: 6

Palindrome: No

Factorization: 3 × 7 × 19 × 53

Divisors: 1, 3, 7, 19, 21, 53, 57, 133, 159, 371

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101001010011011

Octal: 51233

Duodecimal: 102A3

Hexadecimal: 529b

Square: 447195609

Square Root: 145.42008114424914

Classification

Fibonacci: No

Bell Number: Yes

Factorial Number: No

Regular Number: No

Perfect Number: No

Special

Kaprekar Constant: No

Munchausen Constant: No

Armstrong Number: No

Kaprekar Number: No

Catalan Number: No

Vampire Number: No

Taxicab Number: No

Super Prime: No

Friedman Number: No

Fermat Number: No

Cullen Number: No

OEIS Sequences

Bell or exponential numbers: number of ways to partition a set of n labeled elements. A110

Triangle read by rows, Bell transform of Bell numbers. A264428

Aitken's array: triangle of numbers {a(n,k), n >= 0, 0 <= k <= n} read by rows, defined by a(0,0)=1, a(n,0) = a(n-1,n-1), a(n,k) = a(n,k-1) + a(n-1,k-1). A11971

Number T(n,k) of collections of nonempty multisets with a total of n objects of exactly k colors; triangle T(n,k), n>=0, 0<=k<=n, read by rows. A255903

Triangle read by rows: T(n,c) = number of successive equalities in set partitions of n. A56857

Square array A(n,k), n >= 0, k >= 0, read by antidiagonals, where the e.g.f. of column k is 1+g^k+1(x) with g = x-> exp(x)-1. A144150

Number A(n,k) of partitions of the (n+k)-multiset {0,...,0,1,2,...,k} with n 0's; square array A(n,k), n>=0, k>=0, read by antidiagonals. A346426

Total sum T(n,k) of the sizes of all blocks with maximal element k in all set partitions of {1,2,...,n}; triangle T(n,k), n>=1, 1<=k<=n, read by rows. A270701

Total sum T(n,k) of the sizes of all blocks with minimal element k in all set partitions of {1,2,...,n}; triangle T(n,k), n>=1, 1<=k<=n, read by rows. A270702

Number A(n,k) of partitions of the (n+k)-multiset {0,...,0,1,2,...,k} with n 0's into distinct multisets; square array A(n,k), n>=0, k>=0, read by antidiagonals. A346520