6664640410391 has 2 divisors, whose sum is σ = 6664640410392. Its totient is φ = 6664640410390.

The previous prime is 6664640410387. The next prime is 6664640410513. The reversal of 6664640410391 is 1930140464666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6664640410391 - 2² = 6664640410387 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6664640410301) 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, 3332320205195 + 3332320205196.

It is an arithmetic number, because the mean of its divisors is an integer number (3332320205196).

Almost surely, 2^{6664640410391} is an apocalyptic number.

6664640410391 is a deficient number, since it is larger than the sum of its proper divisors (1).

6664640410391 is an equidigital number, since it uses as much as digits as its factorization.

6664640410391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2239488, while the sum is 50.

The spelling of 6664640410391 in words is "six trillion, six hundred sixty-four billion, six hundred forty million, four hundred ten thousand, three hundred ninety-one".