646504 has 16 divisors (see below), whose sum is σ = 1221120. Its totient is φ = 320880.

The previous prime is 646453. The next prime is 646519. The reversal of 646504 is 405646.

It is a happy number.

It is a nialpdrome in base 15.

It is an unprimeable number.

646504 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1497 + ... + 1879.

It is an arithmetic number, because the mean of its divisors is an integer number (76320).

2⁶⁴⁶⁵⁰⁴ is an apocalyptic number.

It is an amenable number.

646504 is a deficient number, since it is larger than the sum of its proper divisors (574616).

646504 is a wasteful number, since it uses less digits than its factorization.

646504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 600 (or 596 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 646504 is about 804.0547245057. The cubic root of 646504 is about 86.4683301484.

The spelling of 646504 in words is "six hundred forty-six thousand, five hundred four".