394578216 has 80 divisors (see below), whose sum is σ = 1126134900. Its totient is φ = 129033216.

The previous prime is 394578193. The next prime is 394578241. The reversal of 394578216 is 612875493.

It can be written as a sum of positive squares in 2 ways, for example, as 394181316 + 396900 = 19854^2 + 630^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 28600 + ... + 40088.

Almost surely, 2^394578216 is an apocalyptic number.

394578216 is a gapful number since it is divisible by the number (36) 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 394578216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (563067450).

394578216 is an abundant number, since it is smaller than the sum of its proper divisors (731556684).

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

394578216 is a wasteful number, since it uses less digits than its factorization.

394578216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11560 (or 11547 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 394578216 is about 19863.9929520729. The cubic root of 394578216 is about 733.4621406432.

The spelling of 394578216 in words is "three hundred ninety-four million, five hundred seventy-eight thousand, two hundred sixteen".