641668207 has 2 divisors, whose sum is σ = 641668208. Its totient is φ = 641668206.

The previous prime is 641668187. The next prime is 641668217. The reversal of 641668207 is 702866146.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 641668207 - 2¹¹ = 641666159 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 641668207.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641668217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320834103 + 320834104.

It is an arithmetic number, because the mean of its divisors is an integer number (320834104).

Almost surely, 2^641668207 is an apocalyptic number.

641668207 is a deficient number, since it is larger than the sum of its proper divisors (1).

641668207 is an equidigital number, since it uses as much as digits as its factorization.

641668207 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96768, while the sum is 40.

The square root of 641668207 is about 25331.1706598807. The cubic root of 641668207 is about 862.5219853529.

The spelling of 641668207 in words is "six hundred forty-one million, six hundred sixty-eight thousand, two hundred seven".