641803920 has 80 divisors (see below), whose sum is σ = 2012014080. Its totient is φ = 169219072.

The previous prime is 641803919. The next prime is 641803931. The reversal of 641803920 is 29308146.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6337 + ... + 36383.

It is an arithmetic number, because the mean of its divisors is an integer number (25150176).

Almost surely, 2^641803920 is an apocalyptic number.

641803920 is a gapful number since it is divisible by the number (60) 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 641803920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1006007040).

641803920 is an abundant number, since it is smaller than the sum of its proper divisors (1370210160).

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

641803920 is a wasteful number, since it uses less digits than its factorization.

641803920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30152 (or 30146 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 641803920 is about 25333.8492929914. The cubic root of 641803920 is about 862.5827889445.

The spelling of 641803920 in words is "six hundred forty-one million, eight hundred three thousand, nine hundred twenty".