How many years would it take to send one email every two minutes, to send 650,000
650,000/2 = 325,000 minutes
325,000/60 ≈ 5416.66666... hours
5416.666.../24 ≈ 225.69444444... days.
225.6944444.../365 ≈ 0.618 year.
Actually, one year does not equal 365 days but instead equals 365.25 days.
She could have mailing lists and so do whole loads at once.