74359...53743 (70-digits)

This number is a prime.

7435961149 1511672232 3924125729 3313331347 3834194214 9150956360 1617653743

The concatenation of the first twenty-five primes with sum of digits congruent to 0(mod 7). Curiously, it remains prime if we concatenate it in the reverse order. Note that the sum of digits of 25 and 70 are both congruent to 0(mod 7). [Antonious]