6561904 has 10 divisors (see below), whose sum is σ = 12713720. Its totient is φ = 3280944.

The previous prime is 6561887. The next prime is 6561911. The reversal of 6561904 is 4091656.

It is a plaindrome in base 13.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 205044 + ... + 205075.

It is an arithmetic number, because the mean of its divisors is an integer number (1271372).

Almost surely, 2^6561904 is an apocalyptic number.

It is an amenable number.

6561904 is a deficient number, since it is larger than the sum of its proper divisors (6151816).

6561904 is a wasteful number, since it uses less digits than its factorization.

6561904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410127 (or 410121 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 6561904 is about 2561.6213615599. The cubic root of 6561904 is about 187.2161417401.

The spelling of 6561904 in words is "six million, five hundred sixty-one thousand, nine hundred four".