Straight from the UA website:

To be considered for the pilot position at United Airlines, you must possess
the following minimum qualifications at the time of application. Those who do not meet the minimum qualifications will not be considered as applicants by United Airlines:

* 1500 hours Total Time - Fixed Wing.
* 1000 hours Multi-engine time (PIC) or Military fighter/trainer (PIC).
* 500 hours Turbine Time.
* 100 hours flown in the past year (Recency of experience).
* Current FCC license.
* Current valid passport.
* Current First Class Medical.
* Current ATP Certificate with Multi-engine land rating (AMEL).
* High school diploma or GED equivalent.
* Legal right to work in the United States without sponsorship.
* A college degree from an accredited school is preferred.

Please note that PIC is defined as Captain/Aircraft Commander of record, not simply the sole manipulator of the controls. United only considers pilot time in fixed wing aircraft toward minimum qualifications.