6543993 has 4 divisors (see below), whose sum is σ = 8725328. Its totient is φ = 4362660.

The previous prime is 6543989. The next prime is 6544003. The reversal of 6543993 is 3993456.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 6543993 - 2² = 6543989 is a prime.

It is a d-powerful number, because it can be written as 6⁸ + 5⁷ + 4¹¹ + 3¹⁰ + 9³ + 9³ + 3¹² .

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6543973) 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, 1090663 + ... + 1090668.

It is an arithmetic number, because the mean of its divisors is an integer number (2181332).

Almost surely, 2^6543993 is an apocalyptic number.

It is an amenable number.

6543993 is a deficient number, since it is larger than the sum of its proper divisors (2181335).

6543993 is a wasteful number, since it uses less digits than its factorization.

6543993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2181334.

The product of its digits is 87480, while the sum is 39.

The square root of 6543993 is about 2558.1229446608. The cubic root of 6543993 is about 187.0456483448.

The spelling of 6543993 in words is "six million, five hundred forty-three thousand, nine hundred ninety-three".