6391543 has 4 divisors (see below), whose sum is σ = 6727960. Its totient is φ = 6055128.

The previous prime is 6391537. The next prime is 6391547. The reversal of 6391543 is 3451936.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6391543 is a prime.

It is a Duffinian number.

6391543 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6391547) by changing a digit.

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

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 168180 + ... + 168217.

It is an arithmetic number, because the mean of its divisors is an integer number (1681990).

Almost surely, 2^6391543 is an apocalyptic number.

6391543 is a deficient number, since it is larger than the sum of its proper divisors (336417).

6391543 is a wasteful number, since it uses less digits than its factorization.

6391543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336416.

The product of its digits is 9720, while the sum is 31.

The square root of 6391543 is about 2528.1501142139. The cubic root of 6391543 is about 185.5817383037.

The spelling of 6391543 in words is "six million, three hundred ninety-one thousand, five hundred forty-three".