Properties of the Number 21465

Twenty-One Thousand Four Hundred Sixty-Five

Basics

Value: 21464 → 21465 → 21466

Parity: odd

Prime: No

Previous Prime: 21433

Next Prime: 21467

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ⁴ × 5 × 53

Divisors: 1, 3, 5, 9, 15, 27, 45, 53, 81, 135

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001111011001

Octal: 51731

Duodecimal: 10509

Hexadecimal: 53d9

Square: 460746225

Square Root: 146.50938536489735

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

Indices of primes followed by a gap (distance to next larger prime) of 44. A320720

Number of integer partitions of n such that for some part k the multiplicity of k exceeds k. A387578

Triangle read by rows, e.g.f. exp(x*(z+3/2))/((exp(3·x/2)+2·cos(sqrt(3)*x/2))/3). A215062

Triangle read by rows. The Hadamard product of A173018 and A349203. A363154

a(n) = (2·n³ + 5·n² - 3·n)/2. A162256

Expansion of (1-q)^k/∏_j=1..k (1-q^j) for k=12. A275643

T(n, k) = A343277(n)*[x^k] p(n, x) where p(n, x) = (1/(n+1))*∑_k=0..n (-1)^k*E1(n, k)*x^{n - k} / binomial(n, k), and E1(n, k) are the Eulerian numbers A123125. Triangle read by rows, for 0 <= k <= n. A342321

Number of partitions of the n-th decimal palindrome into distinct decimal palindromes. A91585

Coefficients of the derivatives of the Eulerian polynomials (with indexing as in A173018). A142706

Numbers k such that k!4 + 2⁴ is prime, where k!4 = k!!!! is the quadruple factorial number (A007662). A291344