Congruência a ≡ b (mod n)
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- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
congruência
About this calculator
This congruence a ≡ b (mod n) calculator checks if the remainder of a division is equal to 0. This means that the difference between two numbers (a and b) is a multiple of a number (n).
The congruence formula is used in Number Theory, a branch of mathematics that studies properties of integers. The congruence is a relation between numbers that is preserved under certain operations.
The congruence is useful for solving problems involving remainders of division and for checking if a number is a multiple of another. This is especially useful in cryptography and in competitive programming.
Note that the congruence is a relation between numbers, not an equality. For example, 5 ≡ 10 (mod 5) is true, because the difference between 5 and 10 (5) is a multiple of 5.
Frequently asked questions
What is congruence?
Congruence is a relation between numbers that is preserved under certain operations. It is used in Number Theory to solve problems involving remainders of division and to verify if a number is a multiple of another.
When to use the congruence calculator?
Use the congruence calculator to solve problems involving remainders of division and to verify if a number is a multiple of another. This is especially useful in cryptography and in competitive programming.
What is the congruence formula?
The congruence formula is used in Number Theory to solve problems involving remainders of division and to verify if a number is a multiple of another.
How does the congruence calculator work?
The congruence calculator checks if the difference between two numbers (a and b) is a multiple of a number (n). This is done using the congruence formula a ≡ b (mod n).
What is the remainder of division?
The remainder of division is the number that remains after dividing one number by another. For example, the remainder of 17 divided by 5 is 2.