646308 has 36 divisors (see below), whose sum is σ = 1760668. Its totient is φ = 198720.

The previous prime is 646307. The next prime is 646309. The reversal of 646308 is 803646.

646308 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (646307) and next prime (646309).

It can be written as a sum of positive squares in 2 ways, for example, as 186624 + 459684 = 432^2 + 678^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a nialpdrome in base 15.

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 11 ways as a sum of consecutive naturals, for example, 223 + ... + 1158.

2⁶⁴⁶³⁰⁸ is an apocalyptic number.

It is an amenable number.

646308 is an abundant number, since it is smaller than the sum of its proper divisors (1114360).

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

646308 is a wasteful number, since it uses less digits than its factorization.

646308 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1404 (or 1399 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 646308 is about 803.9328330153. The cubic root of 646308 is about 86.4595910915.

The spelling of 646308 in words is "six hundred forty-six thousand, three hundred eight".