http://atomicbombmuseum.org/4_survivors.shtml
[In Japan,] a national survey of October 1950 gives a national survivor total of 283,508, with 158,597 for Hiroshima, 124,167 for Nagasaki, and 10 persons who experienced both bombings.
Of Hiroshima’s survivors, 79 percent lived in Hiroshima Prefecture, of whom 98,102 (79%) resided in Hiroshima City. Comparable figures for Nagasaki survivors were 111,294 (89%) in its prefecture, with 96,582 (77%) living in the city.
[From another source:] Within the first two to four months after the bombings, the acute effects of the atomic bombings killed 90,000 - 146,000 people in Hiroshima and 39,000 - 80,000 in Nagasaki; roughly half of the deaths in each city occurred on the first day.
My point? The number of survivors, even of a real (fission) nuke, would be large, probably larger than the number dead. It would be a terrible thing to happen, and medical care for the wounded would lead to national challenges, but it is not the end of the world even for those within 1-3 km of the blast. Go with fusion, a genuine, high-yield thermonuclear device, and all bets are off for several kilometers.
And my point was to keep the questioners expectation low. False hopes and statistics from primitive nuke use may be very misleading for today’s nukes.
You wanna tell him that there is nothing to worry about - all your family and property will be just fine - go back to sleep?