6487391 has 2 divisors, whose sum is σ = 6487392. Its totient is φ = 6487390.

The previous prime is 6487381. The next prime is 6487399. The reversal of 6487391 is 1937846.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6487391 is a prime.

It is a Chen prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6487399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3243695 + 3243696.

It is an arithmetic number, because the mean of its divisors is an integer number (3243696).

Almost surely, 2^6487391 is an apocalyptic number.

6487391 is a deficient number, since it is larger than the sum of its proper divisors (1).

6487391 is an equidigital number, since it uses as much as digits as its factorization.

6487391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 38.

The square root of 6487391 is about 2547.0357280572. The cubic root of 6487391 is about 186.5048047695.

The spelling of 6487391 in words is "six million, four hundred eighty-seven thousand, three hundred ninety-one".