Number 070 6179 0526 is potentially valid
Ofcom records show that numbers starting 070617 are allocated to Sky Telecom Limited. Note that due to number portability if an individual number has moved to a different operator this information is not publicly available.
Ofcom's last recorded change for this number range was November 2009.
The correct way to write the telephone number 07061790526 is 070 6179 0526
For more information on tariffs and usage of numbers starting 07 please visit the page on 07 numbers