641568 has 48 divisors (see below), whose sum is σ = 1735776. Its totient is φ = 207360.

The previous prime is 641551. The next prime is 641579. The reversal of 641568 is 865146.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3855 + ... + 4017.

It is an arithmetic number, because the mean of its divisors is an integer number (36162).

2⁶⁴¹⁵⁶⁸ 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 641568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (867888).

641568 is an abundant number, since it is smaller than the sum of its proper divisors (1094208).

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

641568 is a wasteful number, since it uses less digits than its factorization.

641568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217 (or 209 counting only the distinct ones).

The product of its digits is 5760, while the sum is 30.

The square root of 641568 is about 800.9794004842. The cubic root of 641568 is about 86.2477084037.

The spelling of 641568 in words is "six hundred forty-one thousand, five hundred sixty-eight".