6403543 has 4 divisors (see below), whose sum is σ = 6780240. Its totient is φ = 6026848.

The previous prime is 6403511. The next prime is 6403571. The reversal of 6403543 is 3453046.

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

It is a cyclic number.

It is not a de Polignac number, because 6403543 - 2⁵ = 6403511 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6403343) 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, 188323 + ... + 188356.

It is an arithmetic number, because the mean of its divisors is an integer number (1695060).

Almost surely, 2^6403543 is an apocalyptic number.

6403543 is a deficient number, since it is larger than the sum of its proper divisors (376697).

6403543 is a wasteful number, since it uses less digits than its factorization.

6403543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 376696.

The product of its (nonzero) digits is 4320, while the sum is 25.

The square root of 6403543 is about 2530.5222781078. The cubic root of 6403543 is about 185.6978077519.

Adding to 6403543 its reverse (3453046), we get a palindrome (9856589).

The spelling of 6403543 in words is "six million, four hundred three thousand, five hundred forty-three".