Properties of the Number 28975

Twenty-Eight Thousand Nine Hundred Seventy-Five

Basics

Value: 28974 → 28975 → 28976

Parity: odd

Prime: No

Previous Prime: 28961

Next Prime: 28979

Digit Sum: 31

Digital Root: 4

Palindrome: No

Factorization: 5 ² × 19 × 61

Divisors: 1, 5, 19, 25, 61, 95, 305, 475, 1159, 1525

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 111000100101111

Octal: 70457

Duodecimal: 14927

Hexadecimal: 712f

Square: 839550625

Square Root: 170.220445305492

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

Sum T(n,k) of the entries in the k-th blocks of all set partitions of [n]; triangle T(n,k), n>=1, 1<=k<=n, read by rows. A285362

-5-Knödel numbers. A225509

a(n) = ((5 + 2·sqrt(2))*(3 + sqrt(2))ⁿ + (5 - 2·sqrt(2))*(3 - sqrt(2))ⁿ)/2. A163609

Numbers k such that d(k) > d(k+1) > d(k+2) > d(k+3) > d(k+4), where d(n) is the number of divisors of n. A364720

Number of 5-leaf rooted trees with n levels. A7715

Numbers which are the sums of consecutive fifth powers. A217845

G.f. = b(2)*b(4)*b(6)/(x⁸-x³-x+1), where b(k) = (1-x^k)/(1-x). A266338

Sum of the entries in the sixth blocks of all set partitions of [n]. A285368

Array read by ascending antidiagonals: A(n, k) = HurwitzZeta(-n, k) - HurwitzZeta(-n, k+n) with k >= 0. A391310

Numbers k such that k and k+1 have the same sum of 5-smooth divisors. A355713