• The game's top prize has been growing for more than three months.
• The chance of a single ticket hitting all six numbers drawn is about one in 302 million.
• If you win, there are some things to consider before claiming your prize.

Sure, the chance of your ticket hitting the Mega Millions jackpot is tiny — roughly one in 302 million.

Nevertheless, it's worth considering what you'd do if you manage to beat the odds. For Friday night's drawing, matching all six numbers pulled would mean landing $421 million.

The amount has been rolling higher since late October, when $108 million was won. That marked the last of six jackpots awarded in 2021, which ranged from $55 million to $1.05 billion.

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If you end up joining the short list of top-prize winners, there are some things to consider before doing much of anything.

For starters, lottery tickets are considered "bearer instruments," which means whoever holds it is considered the owner. This means you need to earnestly protect it.

Take a picture of yourself with the winning ticket, said certified financial planner Joe Buhrmann, senior financial planning consultant at eMoney Advisor. Also put the ticket somewhere secure — such as in a safety deposit box — until it's time to claim your windfall.

Additionally, you may want to sign the back of the ticket. Just be aware that in some states, doing so could interfere with your ability to claim the prize via a trust or other legal entity that would shield your identity from the public.

It's also worth sharing the exciting news with as few people as possible. If you won't be able to remain anonymous — it depends on state laws — you need to consider how to avoid becoming a target for scammers as well as long-lost family and friends.

"You may have been friendless and unknown to passers-by on the streets," Buhrmann said. "That will all change when you're announced as the winner." 

You also should turn to experienced professionals to help guide you through the claiming process and the many facets of protecting your windfall. Your team should include an attorney, financial advisor, tax advisor and insurance professional. 

This group can help you determine whether to take your winnings as a lump sum or as 30 payments spread over 29 years. Most lottery winners choose the immediate, reduced cash amount. For Mega Millions' $421 million jackpot, the cash option is $290.9 million.

Either way, the money would face a 24% federal tax withholding before it reaches you. For this jackpot, taking the cash would mean about $69.8 million getting shaved off the top, leaving you with a cool $221.1 million. Depending where you won the jackpot, there also may be state taxes withheld.

Additional federal income taxes would likely also be due at tax time, given the top rate of 37%. There also may be more due in state taxes, depending on the jurisdiction's rate of withholding.

It's also worth giving some thought to how your life is going to change — not just from a financial aspect.

"Consider how this newfound wealth will change your marriage, family and dynamics with friends and neighbors," Buhrmann said.

You may even want to seek guidance from a financial therapist or mental health professional to help you deal with the stress that comes with winning, he said.

Meanwhile, Powerball's jackpot is $104 million for Saturday night's drawing. The cash option is $72.5 million. As with Mega Millions, the chance of a single ticket winning the top prize is tiny: one in 292 million.