A monotonic counter stores N binary words representing a value in N memory cells. When i memory cells of consecutive ranks between k modulo N and k+i modulo N each represent a value complementary to a null value, the counter is incremented by erasing a value of a memory cell of rank k+i+1 modulo N. When i+1 memory cells of consecutive ranks between k+1 modulo N and k+i+1 modulo N each represent the value complementary to the null value, the counter is incremented by incrementing a value of a memory cell of rank k modulo N by two step sizes and storing a result in a memory cell of rank k+1 modulo N, wherein, N is an integer greater than or equal to five, k is an integer, and i is an integer between 2 and N−3.