391785016 has 96 divisors (see below), whose sum is σ = 910224000. Its totient is φ = 154395072.

The previous prime is 391784989. The next prime is 391785047. The reversal of 391785016 is 610587193.

It is a self number, because there is not a number n which added to its sum of digits gives 391785016.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4959265 + ... + 4959343.

It is an arithmetic number, because the mean of its divisors is an integer number (9481500).

Almost surely, 2^391785016 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 391785016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (455112000).

391785016 is an abundant number, since it is smaller than the sum of its proper divisors (518438984).

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

391785016 is a wasteful number, since it uses less digits than its factorization.

391785016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249 (or 166 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 40.

The square root of 391785016 is about 19793.5599627758. The cubic root of 391785016 is about 731.7273263520.

The spelling of 391785016 in words is "three hundred ninety-one million, seven hundred eighty-five thousand, sixteen".