Belphegor's prime

Common card · No. 346195

Belphegor's prime is the palindromic prime number 1000000000000066600000000000001 (1030 + 666 × 1014 + 1), a number which reads the same both backwards and forwards and is only divisible by itself and one. In the short scale, this number would be named "one nonillion, sixty-six quadrillion, six hundred trillion one." In the long scale, this number's name would be "one quintillion, sixty-six billiard, six hundred billion one."

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