6503993 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.
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, and also a brilliant number, because the two primes have the same length.
It is a cyclic number.
It is a Duffinian number.
It is a Curzon number.
Almost surely, 26503993 is an apocalyptic number.
It is an amenable number.
6503993 is a wasteful number, since it uses less digits than its factorization.
6503993 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 5574.
The square root of 6503993 is about 2550.2927282961. The cubic root of 6503993 is about 186.6637651902.
The spelling of 6503993 in words is "six million, five hundred three thousand, nine hundred ninety-three".