645926641907 has 2 divisors, whose sum is σ = 645926641908. Its totient is φ = 645926641906.

The previous prime is 645926641847. The next prime is 645926641961. The reversal of 645926641907 is 709146629546.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 645926641907 - 2²⁸ = 645658206451 is a prime.

It is not a weakly prime, because it can be changed into another prime (645926641967) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322963320953 + 322963320954.

It is an arithmetic number, because the mean of its divisors is an integer number (322963320954).

Almost surely, 2^645926641907 is an apocalyptic number.

645926641907 is a deficient number, since it is larger than the sum of its proper divisors (1).

645926641907 is an equidigital number, since it uses as much as digits as its factorization.

645926641907 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19595520, while the sum is 59.

The spelling of 645926641907 in words is "six hundred forty-five billion, nine hundred twenty-six million, six hundred forty-one thousand, nine hundred seven".