6487891 has 4 divisors (see below), whose sum is σ = 6494400. Its totient is φ = 6481384.

The previous prime is 6487879. The next prime is 6487903. The reversal of 6487891 is 1987846.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is an interprime number because it is at equal distance from previous prime (6487879) and next prime (6487903).

It is a cyclic number.

It is not a de Polignac number, because 6487891 - 2⁷ = 6487763 is a prime.

It is a Duffinian number.

6487891 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (6487841) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1411 + ... + 3868.

It is an arithmetic number, because the mean of its divisors is an integer number (1623600).

Almost surely, 2^6487891 is an apocalyptic number.

6487891 is a deficient number, since it is larger than the sum of its proper divisors (6509).

6487891 is a wasteful number, since it uses less digits than its factorization.

6487891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6508.

The product of its digits is 96768, while the sum is 43.

The square root of 6487891 is about 2547.1338794810. The cubic root of 6487891 is about 186.5095961156.

The spelling of 6487891 in words is "six million, four hundred eighty-seven thousand, eight hundred ninety-one".