394005820 has 48 divisors (see below), whose sum is σ = 903309120. Its totient is φ = 143479296.

The previous prime is 394005811. The next prime is 394005853. The reversal of 394005820 is 28500493.

It is a congruent number.

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, 8601 + ... + 29359.

It is an arithmetic number, because the mean of its divisors is an integer number (18818940).

Almost surely, 2^394005820 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 394005820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (451654560).

394005820 is an abundant number, since it is smaller than the sum of its proper divisors (509303300).

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

394005820 is a wasteful number, since it uses less digits than its factorization.

394005820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20854 (or 20852 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 394005820 is about 19849.5798444199. The cubic root of 394005820 is about 733.1073026991.

The spelling of 394005820 in words is "three hundred ninety-four million, five thousand, eight hundred twenty".