Properties of the Number 21428

Twenty-One Thousand Four Hundred Twenty-Eight

Basics

Value: 21427 → 21428 → 21429

Parity: even

Prime: No

Previous Prime: 21419

Next Prime: 21433

Digit Sum: 17

Digital Root: 8

Palindrome: No

Factorization: 2 ² × 11 × 487

Divisors: 1, 2, 4, 11, 22, 44, 487, 974, 1948, 5357

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101001110110100

Octal: 51664

Duodecimal: 10498

Hexadecimal: 53b4

Square: 459159184

Square Root: 146.3830591291219

Classification

Fibonacci: No

Bell Number: No

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

Sequence is defined by property that (a0,a1,a2,a3,...) = binomial transform of (a0,a0,a1,a1,a2,a2,a3,a3,...). A51163

T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock having the absolute values of all six edge and diagonal differences no larger than 1. A234161

Triangle, read by rows, equal to the matrix inverse of Q=A113381. A114158

Numbers which are the sum of two positive cubes and divisible by 11. A101852

a(n) = n³ + (n+2)³. A153976

a(n) = 4·n*(4·n² + 3). A271636

Sequence defined by the recurrence formula a(n+1)=sum(a(p)*a(n-p)+k,p=0..n)+l for n>=1, with here a(0)=1, a(1)=2, k=0 and l=-1. A176678

Number of (n+1) X (2+1) 0..3 arrays with every 2 X 2 subblock having the absolute values of all six edge and diagonal differences no larger than 1. A234155

Number of (n+1)X(3+1) 0..3 arrays with every 2X2 subblock having the absolute values of all six edge and diagonal differences no larger than 1. A234156

Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 443", based on the 5-celled von Neumann neighborhood. A272227