393994784716640 has 96 divisors (see below), whose sum is σ = 933701003746560. Its totient is φ = 157109163369984.

The previous prime is 393994784716639. The next prime is 393994784716667. The reversal of 393994784716640 is 46617487499393.

It is a Harshad number since it is a multiple of its sum of digits (80).

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, 180598427 + ... + 182767013.

It is an arithmetic number, because the mean of its divisors is an integer number (9726052122360).

Almost surely, 2^{393994784716640} 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 393994784716640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (466850501873280).

393994784716640 is an abundant number, since it is smaller than the sum of its proper divisors (539706219029920).

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

393994784716640 is a wasteful number, since it uses less digits than its factorization.

393994784716640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2172124 (or 2172116 counting only the distinct ones).

The product of its (nonzero) digits is 5925685248, while the sum is 80.

The spelling of 393994784716640 in words is "three hundred ninety-three trillion, nine hundred ninety-four billion, seven hundred eighty-four million, seven hundred sixteen thousand, six hundred forty".