Properties of the Number -30

Thirty

Basics

Value: -31 → -30 → -29

Parity: even

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 3

Digital Root: 3

Palindrome: No

Factorization: 2 × 3 × 5

Divisors: 1, 2, 3, 5, 6, 10, 15, 30

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -11110

Octal: -36

Duodecimal: -26

Hexadecimal: -1e

Square: 900

Square Root: 5.477225575051661

Classification

Fibonacci: No

Bell Number: No

Factorial Number: No

Regular Number: Yes

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

Dirichlet inverse of Euler totient function (A000010). A23900

Abundance of n, or (sum of divisors of n) - 2n. A33880

Canonical enumeration of integers: interleaved positive and negative integers with zero prepended. A1057

a(n) = n * μ(n), where μ is the Möbius function A008683. A55615

a(0) = 0; thereafter a(n) is the least integer (in absolute value) not yet in the sequence such that the absolute difference between a(n-1) and a(n) is a square; in case of a tie, preference is given to the positive value. A377091

Generalized sum of divisors function: excess of sum of odd divisors of n over sum of even divisors of n. A2129

Monic integer version of Chebyshev T-polynomials (increasing powers). A127672

a(n) = ∑_d∣n (-1)^d-1*d². A321543

a(n) = 2 - n. A22958

Product of A049310 and A007318 as lower triangular matrices. A101950