394702643664 has 800 divisors, whose sum is σ = 1395305742336. Its totient is φ = 105345515520.

The previous prime is 394702643663. The next prime is 394702643677. The reversal of 394702643664 is 466346207493.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 394702643664.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (394702643663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 1535807824 + ... + 1535808080.

Almost surely, 2^394702643664 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 394702643664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (697652871168).

394702643664 is an abundant number, since it is smaller than the sum of its proper divisors (1000603098672).

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

394702643664 is a wasteful number, since it uses less digits than its factorization.

394702643664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 485 (or 470 counting only the distinct ones).

The product of its (nonzero) digits is 15676416, while the sum is 54.

The spelling of 394702643664 in words is "three hundred ninety-four billion, seven hundred two million, six hundred forty-three thousand, six hundred sixty-four".