641820396 has 96 divisors (see below), whose sum is σ = 1765919232. Its totient is φ = 177615360.

The previous prime is 641820379. The next prime is 641820401. The reversal of 641820396 is 693028146.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 540115 + ... + 541301.

It is an arithmetic number, because the mean of its divisors is an integer number (18394992).

Almost surely, 2^641820396 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 641820396, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (882959616).

641820396 is an abundant number, since it is smaller than the sum of its proper divisors (1124098836).

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

641820396 is a wasteful number, since it uses less digits than its factorization.

641820396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1399 (or 1397 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 39.

The square root of 641820396 is about 25334.1744684922. The cubic root of 641820396 is about 862.5901701149.

The spelling of 641820396 in words is "six hundred forty-one million, eight hundred twenty thousand, three hundred ninety-six".