🔢 Number & Reference

Number & Reference Calculators

Explore number conversions and reference tasks involving Roman numerals, number words, primes, factors, sequences and different number systems. These tools can help with study, data checking and quick reference. Confirm the accepted input range and notation, especially when working with very large numbers or specialized mathematical conventions.

30 calculators Free tools Global & practical

Number Conversion & Representation

7 tools

Number to Words Converter Convert numbers into words for documents, forms and everyday use. Words to Number Converter Convert written number words into their numeric form. Roman Numeral Converter Convert between Roman numerals and standard numbers. Number Base Converter Convert integers between binary, octal, decimal, hexadecimal and other bases. Binary Converter Convert binary values to decimal, octal and hexadecimal, and back. Hexadecimal Converter Convert hexadecimal integers to decimal, binary and octal. Scientific Notation Converter Convert numbers between ordinary decimal and scientific notation.

Prime & Factor Tools

12 tools

Prime Number Checker Check whether an integer is prime or composite. Prime Number Generator Generate prime numbers within a selected range. Prime Factorization Calculator Break an integer into its prime factors. Factors Calculator Find all positive factors of an integer. Divisors Calculator List the positive divisors of an integer. Number of Divisors Calculator Find how many positive divisors an integer has. Sum of Divisors Calculator Calculate the sum of all positive divisors. GCD / HCF Calculator Find the greatest common divisor, HCF or GCF of integers. LCM Calculator Find the least common multiple of two or more integers. GCD & LCM Calculator Calculate both the GCD and LCM of multiple integers. Coprime Checker Check whether two or more integers are relatively prime. Divisibility Checker Check whether an integer is exactly divisible by another.

Number Properties

6 tools

Digit Sum Calculator Add the digits of an integer and calculate its digit sum. Even / Odd Checker Determine whether an integer is even or odd. Perfect Number Checker Check whether an integer equals the sum of its proper divisors. Perfect Square Checker Check whether an integer is a perfect square. Palindrome Number Checker Check whether a number reads the same forwards and backwards. Fibonacci Sequence Generator Generate Fibonacci numbers and view the sequence.

Advanced Number Theory

5 tools

Modulo Calculator Calculate remainders and modular results for integer calculations. Euler Totient Calculator Calculate Euler's totient function for a positive integer. Modular Inverse Calculator Find the modular inverse when it exists. Extended GCD Calculator Calculate the extended Euclidean algorithm and Bézout coefficients. Chinese Remainder Theorem Calculator Solve compatible systems of simultaneous integer congruences.