641708928 has 384 divisors, whose sum is σ = 2321879040. Its totient is φ = 165888000.

The previous prime is 641708887. The next prime is 641708953. The reversal of 641708928 is 829807146.

641708928 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 (384).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4249653 + ... + 4249803.

It is an arithmetic number, because the mean of its divisors is an integer number (6046560).

Almost surely, 2^641708928 is an apocalyptic number.

641708928 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 641708928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1160939520).

641708928 is an abundant number, since it is smaller than the sum of its proper divisors (1680170112).

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

641708928 is a wasteful number, since it uses less digits than its factorization.

641708928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226 (or 211 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The square root of 641708928 is about 25331.9744196934. The cubic root of 641708928 is about 862.5402305116.

The spelling of 641708928 in words is "six hundred forty-one million, seven hundred eight thousand, nine hundred twenty-eight".