The chances of picking one correct number out of 44 is 1/44. For picking a second correct number is 1/43, a third, 1/42,... so probability of 5 correct numbers is 1/(44×43×42×41×40) then picking an incorrect number we multiply by 38/39, but the incorrect number could be any one of 6 places so we multiply the final result by 6:
19/423543120=4.4860×10⁻⁸ or 0.000000044860.