Properties of the Number 2661

Two Thousand Six Hundred Sixty-One

Basics

Value: 2660 → 2661 → 2662

Parity: odd

Prime: No

Previous Prime: 2659

Next Prime: 2663

Digit Sum: 15

Digital Root: 6

Palindrome: No

Factorization: 3 × 887

Divisors: 1, 3, 887, 2661

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101001100101

Octal: 5145

Duodecimal: 1659

Hexadecimal: a65

Square: 7080921

Square Root: 51.58488150611572

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

a(n) = least k such that the remainder when 20^k is divided by k is n. A128160

Discriminants of real quadratic fields with class number 1 and related continued fraction period length of 24. A51965

Pinwheel numbers: a(n) = 2·n² + 6·n + 1. A59993

List of binary palindromes of even length (written in base 10). A48701

a(1) = 0, a(2) = 1, and for n > 2, a(n) = 2·a(A252463(n)) + [n == 1 (mod 4)]. A292385

Numbers k such that lcm(1,2,3,...,k)/5 equals the denominator of the k-th harmonic number H(k). A112814

T(n,k)=Number of nXk 0..2 arrays with rows nondecreasing and antidiagonals unimodal. A224012

Number of integer partitions of n such that every pair of distinct parts has a different product. A325856

Intrinsic 12-palindromes: n is an intrinsic k-palindrome if it is a k-digit palindrome in some base. A60949

Numbers k that are the products of two distinct primes such that 2·k-1, 4·k-3 and 8·k-7 are also products of two distinct primes. A177212