646608 has 40 divisors (see below), whose sum is σ = 1760800. Its totient is φ = 203904.

The previous prime is 646577. The next prime is 646609. The reversal of 646608 is 806646.

It is a happy number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 646608.

It is not an unprimeable number, because it can be changed into a prime (646609) by changing a digit.

646608 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 7 ways as a sum of consecutive naturals, for example, 558 + ... + 1266.

It is an arithmetic number, because the mean of its divisors is an integer number (44020).

2⁶⁴⁶⁶⁰⁸ 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 646608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (880400).

646608 is an abundant number, since it is smaller than the sum of its proper divisors (1114192).

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

646608 is a wasteful number, since it uses less digits than its factorization.

646608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 739 (or 733 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 646608 is about 804.1193941201. The cubic root of 646608 is about 86.4729664818.

The spelling of 646608 in words is "six hundred forty-six thousand, six hundred eight".