645104563431331 has 2 divisors, whose sum is σ = 645104563431332. Its totient is φ = 645104563431330.

The previous prime is 645104563431281. The next prime is 645104563431343. The reversal of 645104563431331 is 133134365401546.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 645104563431331 - 2¹³ = 645104563423139 is a prime.

It is a super-2 number, since 2×645104563431331² (a number of 30 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (645104563431631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322552281715665 + 322552281715666.

It is an arithmetic number, because the mean of its divisors is an integer number (322552281715666).

Almost surely, 2^{645104563431331} is an apocalyptic number.

645104563431331 is a deficient number, since it is larger than the sum of its proper divisors (1).

645104563431331 is an equidigital number, since it uses as much as digits as its factorization.

645104563431331 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4665600, while the sum is 49.

The spelling of 645104563431331 in words is "six hundred forty-five trillion, one hundred four billion, five hundred sixty-three million, four hundred thirty-one thousand, three hundred thirty-one".