Umm Salama (Allah be pleased with her) reported that Allah's Messenger (ﷺ) married her, and he (the narrator) made mention of so many things in this connection (and one of them was this) that he said: If you desire that I spend a week with you, I shall have to spend a week with my (other) wives, and if spend a week with you, I shall have to spend a week with my (other) wives.
Source: sunnah.com
Other translations
Arabic
حَدَّثَنِي أَبُو كُرَيْبٍ، مُحَمَّدُ بْنُ الْعَلاَءِ حَدَّثَنَا حَفْصٌ، - يَعْنِي ابْنَ غِيَاثٍ - عَنْ عَبْدِ، الْوَاحِدِ بْنِ أَيْمَنَ عَنْ أَبِي بَكْرِ بْنِ عَبْدِ الرَّحْمَنِ بْنِ الْحَارِثِ بْنِ هِشَامٍ، عَنْ أُمِّ سَلَمَةَ، ذَكَرَ أَنَّصلى الله عليه وسلم تَزَوَّجَهَا وَذَكَرَ أَشْيَاءَ هَذَا فِيهِ قَالَ " إِنْ شِئْتِ أَنْ أُسَبِّعَ لَكِ وَأُسَبِّعَ لِنِسَائِي وَإِنْ سَبَّعْتُ لَكِ سَبَّعْتُ لِنِسَائِي " .
sunnah.com