Quirkulator

Number Theory Calculators

19 calculators covering primes, factors, GCD, LCM and rounding, each with its formula and worked examples.

Number Theory Calculators brings together 19 calculators for primes, factors, GCD, LCM and rounding, including Absolute Change Calculator, Exponent Calculator, Least Common Multiple Calculator and Number to Words Converter.

Each calculation gets its own page, with its own inputs, its own worked examples and its own explanation of what the answer means. The formula is printed on the page rather than hidden in the code, so a result you disagree with can be argued with rather than merely distrusted.

All 19 pages compute in your browser: nothing you type is sent anywhere, and results update as you edit. Each one carries worked examples, interpretation bands where a score needs context, and a FAQ answering what people actually ask about that calculation.

The collection is part of Math & Statistics, and every page links to the neighbouring calculations you usually need next.

19 pages in this collection

Absolute Change CalculatorMeasure the raw gap between two values and the order of magnitude that separates them.Aspect Ratio CalculatorReduce width and height to a named ratio and see which standard format it matches.Digit Sum CalculatorAdd the digits of a number, reduce it to a digital root and test divisibility with it.Exponent CalculatorRaise a number to any power, including negative and fractional exponents.Fibonacci Term CalculatorFind any term of the Fibonacci sequence and watch the ratio settle on the golden ratio.GCD and LCM CalculatorFind the greatest common divisor and lowest common multiple of two numbers.Greatest Common Divisor CalculatorThe largest number that divides both values exactly, via the Euclidean algorithm.Least Common Multiple CalculatorThe smallest number that both values divide into exactly.Logarithm CalculatorFind a logarithm in any base and read it as the number of digits or doublings involved.Modulo CalculatorFind the remainder after division, including the negative case where languages disagree.Nth Root CalculatorTake any root of a number and read it as the growth rate it represents.Number to Words ConverterWrite a number out in full English words, as used on cheques and contracts.Prime Factorisation CalculatorBreak a number into its prime powers and read off how many divisors it has.Prime Number CheckerTest whether a number is prime and, if not, find its prime factors.Roman Numeral ConverterConvert numbers into Roman numerals and see the subtractive pairs used.Rounding CalculatorRound to a chosen place with the rule you actually want, including banker's rounding.Scientific Notation ConverterConvert between ordinary numbers and scientific notation.Significant Figures CalculatorRound a value to a chosen number of significant figures.Square Root CalculatorTake a square root, test for a perfect square and see the surd in simplified form.

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