Why 26*i + 1 in Multiplicative inverse of a number in C?

Question

When i was exploring C language i found a code on web ( https://www.cprograms4future.com/p/multiplicative-inverse.html ) and when i tried to learn the i logic i failed,

means why they use (i*26)+ 1 to find multiplicative Inverse,
Why 26??
Is this a special number?

Code:
https://code.sololearn.com/ccdTM2gCzupZ/?ref=app

Answer 1

Wikipedia: "In mathematics, a multiplicative inverse or reciprocal for a number x, denoted by 1/x or x−1, is a number which when multiplied by x yields the multiplicative identity, 1."

The code gives 3 is 9, 4 is 26....