646944 has 48 divisors (see below), whose sum is σ = 1778112. Its totient is φ = 205568.

The previous prime is 646937. The next prime is 646957. The reversal of 646944 is 449646.

646944 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (48).

It is an Ulam number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 646944.

It is an unprimeable number.

646944 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2062 + ... + 2354.

It is an arithmetic number, because the mean of its divisors is an integer number (37044).

2⁶⁴⁶⁹⁴⁴ 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 646944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (889056).

646944 is an abundant number, since it is smaller than the sum of its proper divisors (1131168).

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

646944 is a wasteful number, since it uses less digits than its factorization.

646944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 329 (or 321 counting only the distinct ones).

The product of its digits is 20736, while the sum is 33.

The square root of 646944 is about 804.3282911846. The cubic root of 646944 is about 86.4879420082.

The spelling of 646944 in words is "six hundred forty-six thousand, nine hundred forty-four".