Properties of the Number 42640

Forty-Two Thousand Six Hundred Forty

Basics

Value: 42639 → 42640 → 42641

Parity: even

Prime: No

Previous Prime: 42611

Next Prime: 42641

Digit Sum: 16

Digital Root: 7

Palindrome: No

Factorization: 2 ⁴ × 5 × 13 × 41

Divisors: 1, 2, 4, 5, 8, 10, 13, 16, 20, 26

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 1010011010010000

Octal: 123220

Duodecimal: 20814

Hexadecimal: a690

Square: 1818169600

Square Root: 206.49455198624491

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

Number of bracelets (turnover necklaces) of n beads of 2 colors, 7 of them black. A32280

a(n) = 2·n*(n+1)*(n+2)/3. A210440

Period of the Fibonacci n-step sequence mod n. A351657

Partial sums of the odd triangular numbers (A014493). A352116

a(n) = (7·n+2)*(7·n+5) = 49·n² + 49·n + 10. A177060

Number of -n..n arrays of 4 elements with zero sum and no two neighbors summing to zero. A199833

Number of labeled totally ordered semigroups with n elements. A84965

Padovan like sequence: a(n) = a(n-2) + a(n-3) for n>3, a(1)=2, a(2)=2, a(3)=0. A276275

Numerators of continued fraction convergents to sqrt(850). A42640

Number of permutations of 5 indistinguishable copies of 1..n with exactly 4 adjacent element pairs in decreasing order. A151649