6388391 has 2 divisors, whose sum is σ = 6388392. Its totient is φ = 6388390.

The previous prime is 6388373. The next prime is 6388399. The reversal of 6388391 is 1938836.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6388391 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6388399) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3194195 + 3194196.

It is an arithmetic number, because the mean of its divisors is an integer number (3194196).

Almost surely, 2^6388391 is an apocalyptic number.

6388391 is a deficient number, since it is larger than the sum of its proper divisors (1).

6388391 is an equidigital number, since it uses as much as digits as its factorization.

6388391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31104, while the sum is 38.

The square root of 6388391 is about 2527.5266566349. The cubic root of 6388391 is about 185.5512266405.

The spelling of 6388391 in words is "six million, three hundred eighty-eight thousand, three hundred ninety-one".