394978220 has 192 divisors, whose sum is σ = 1076275200. Its totient is φ = 120911616.

The previous prime is 394978201. The next prime is 394978229. The reversal of 394978220 is 22879493.

It is not an unprimeable number, because it can be changed into a prime (394978229) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3834689 + ... + 3834791.

It is an arithmetic number, because the mean of its divisors is an integer number (5605600).

Almost surely, 2^394978220 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 394978220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (538137600).

394978220 is an abundant number, since it is smaller than the sum of its proper divisors (681296980).

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

394978220 is a wasteful number, since it uses less digits than its factorization.

394978220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189 (or 173 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 44.

The square root of 394978220 is about 19874.0589714331. The cubic root of 394978220 is about 733.7099062262.

The spelling of 394978220 in words is "three hundred ninety-four million, nine hundred seventy-eight thousand, two hundred twenty".