394569978656 has 96 divisors (see below), whose sum is σ = 927996652800. Its totient is φ = 164976806400.

The previous prime is 394569978641. The next prime is 394569978667. The reversal of 394569978656 is 656879965493.

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, 11621 + ... + 888411.

It is an arithmetic number, because the mean of its divisors is an integer number (9666631800).

Almost surely, 2^394569978656 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 394569978656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (463998326400).

394569978656 is an abundant number, since it is smaller than the sum of its proper divisors (533426674144).

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

394569978656 is an equidigital number, since it uses as much as digits as its factorization.

394569978656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 876863 (or 876841 counting only the distinct ones).

The product of its digits is 2645395200, while the sum is 77.

The spelling of 394569978656 in words is "three hundred ninety-four billion, five hundred sixty-nine million, nine hundred seventy-eight thousand, six hundred fifty-six".