Properties of the Number -7021

Twenty-One

Basics

Value: -7022 → -7021 → -7020

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 10

Digital Root: 1

Palindrome: No

Factorization: 7 × 17 × 59

Divisors: 1, 7, 17, 59, 119, 413, 1003, 7021

Polygonal

Triangular: Yes

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -1101101101101

Octal: -15555

Duodecimal: -4091

Hexadecimal: -1b6d

Square: 49294441

Square Root: 83.79140767405688

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

Successive minima of partial sum of harmonic series Sum (μ(n)/n) are approximately 1/a(n). A71758

Centered 9-gonal (also known as nonagonal or enneagonal) numbers. Every third triangular number, starting with a(1)=1. A60544

Numbers whose binary expansion generates rotationally symmetric XOR-triangles. A334556

a(n) = (2·n-1)*(4·n-1). A33567

Centered 20-gonal (or icosagonal) numbers. A69133

Inverse Mertens function: smallest k such that |M(k)| = n, where M(x) is Mertens's function A002321. A51402

A(n,k) is the n-th positive integer that has exactly k representations of the form 1 + p1 * (1 + p2* ... * (1 + p_j)...), where [p1, ..., p_j] is a (possibly empty) list of distinct primes; square array A(n,k), n>=1, k>=0, read by antidiagonals. A317390

Smallest value of·such that M(x) = -n, where M(x) is Mertens's function A002321. A51401

Positive integers not expressible as the sum of a prime and a triangular number. A76768

Unary-binary representation of Stern polynomials: a(n) = A156552(A260443(n)). A277020