646304 has 24 divisors (see below), whose sum is σ = 1340640. Its totient is φ = 305856.

The previous prime is 646301. The next prime is 646307. The reversal of 646304 is 403646.

It is an interprime number because it is at equal distance from previous prime (646301) and next prime (646307).

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 646304.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646301) 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, 77 + ... + 1139.

It is an arithmetic number, because the mean of its divisors is an integer number (55860).

2⁶⁴⁶³⁰⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646304, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (670320).

646304 is an abundant number, since it is smaller than the sum of its proper divisors (694336).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

646304 is a wasteful number, since it uses less digits than its factorization.

646304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1092 (or 1084 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 23.

The square root of 646304 is about 803.9303452414. The cubic root of 646304 is about 86.4594127250.

The spelling of 646304 in words is "six hundred forty-six thousand, three hundred four".