Singer Robbie Williams has revealed that he is dyslexic when it comes to digits. He says he has problems in doing simple sums.

"I'm numerically dyslexic. I can't add or subtract. I always get in trouble because I don't know my kids' birth dates and I don't know our anniversary and I don't know my wife's birthday," he said, reports thesun.co.uk.

"I can't even remember our house in Los Angeles. It has four digits for the start of the address and I can't ever remember what those digits are," he added.

During a podcast, he said he is going to increase the number of his tattoos by getting important dates inked on him as a reminder.

He also compared his life to Christopher Nolan's cult thriller of 2000, "Memento", about a man who loses his memory every 15 minutes.

"I'm going to get them all tattooed, all of those dates, so I know them and have them, (be)cause every day is like 'Memento' to me," said the singer.