A, M, T, I represent different non-zero digits. It is given that
$$A+M+T+I=11$$,
$$A+M+I=10$$,
$$A+M=1$$.
Further in the following addition only one digit is given.

From the three given equations, subtracting pairs gives $$T=1$$ and $$I=5$$, and then $$A+M=5$$. Setting up the column addition of the decreasing-length numbers AMTI, AMT, AM, A (each contributing digits according to their place value) and working through the carries with the known digit sum in the hundred-thousands place forces $$A=2$$ and $$M=3$$. This gives the full sum as 35725792.