6543503 has 2 divisors, whose sum is σ = 6543504. Its totient is φ = 6543502.

The previous prime is 6543499. The next prime is 6543517. The reversal of 6543503 is 3053456.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6543503 - 2² = 6543499 is a prime.

It is a super-2 number, since 2×6543503² = 85634863022018, which contains 22 as substring.

It is equal to p₄₄₇₅₄₂ and since 6543503 and 447542 have the same sum of digits, it is a Honaker prime.

It is a plaindrome in base 12.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6543533) 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 as a sum of consecutive naturals, namely, 3271751 + 3271752.

It is an arithmetic number, because the mean of its divisors is an integer number (3271752).

Almost surely, 2^6543503 is an apocalyptic number.

6543503 is a deficient number, since it is larger than the sum of its proper divisors (1).

6543503 is an equidigital number, since it uses as much as digits as its factorization.

6543503 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5400, while the sum is 26.

The square root of 6543503 is about 2558.0271695195. The cubic root of 6543503 is about 187.0409797042.

Adding to 6543503 its reverse (3053456), we get a palindrome (9596959).

The spelling of 6543503 in words is "six million, five hundred forty-three thousand, five hundred three".