6684906391 has 2 divisors, whose sum is σ = 6684906392. Its totient is φ = 6684906390.

The previous prime is 6684906383. The next prime is 6684906407. The reversal of 6684906391 is 1936094866.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6684906391 - 2³ = 6684906383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6684906301) 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, 3342453195 + 3342453196.

It is an arithmetic number, because the mean of its divisors is an integer number (3342453196).

Almost surely, 2^6684906391 is an apocalyptic number.

6684906391 is a deficient number, since it is larger than the sum of its proper divisors (1).

6684906391 is an equidigital number, since it uses as much as digits as its factorization.

6684906391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1679616, while the sum is 52.

The square root of 6684906391 is about 81761.2768430141. The cubic root of 6684906391 is about 1883.7869185577.

The spelling of 6684906391 in words is "six billion, six hundred eighty-four million, nine hundred six thousand, three hundred ninety-one".