"Not only does working longer mean more contributions and more compounding, but the longer you can defer drawing assets from your portfolio, the more you improve its longevity," says Christine Benz, director of personal finance at Morningstar...

If you're 55 or older {I think they mean younger}, you won't reach the full retirement age for Social Security benefits until age 66 1/2 or 67. So retiring at 68 or even 70 may not seem like much of a stretch.

Delaying retirement beyond your full retirement age — until you're required to take distributions at age 70 — can increase your Social Security benefits by 8 percent a year, plus these benefits are largely tax-exempt.

By retiring at age 70, you'd receive nearly double the annual Social Security as you have received if you took early retirement at age 62.