394180858640 has 40 divisors (see below), whose sum is σ = 941239976280. Its totient is φ = 153410927616.

The previous prime is 394180858583. The next prime is 394180858651. The reversal of 394180858640 is 46858081493.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 52058810896 + 342122047744 = 228164^2 + 584912^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 66581645 + ... + 66587564.

It is an arithmetic number, because the mean of its divisors is an integer number (23530999407).

Almost surely, 2^394180858640 is an apocalyptic number.

It is an amenable number.

394180858640 is an abundant number, since it is smaller than the sum of its proper divisors (547059117640).

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

394180858640 is a wasteful number, since it uses less digits than its factorization.

394180858640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133169259 (or 133169253 counting only the distinct ones).

The product of its (nonzero) digits is 6635520, while the sum is 56.

The spelling of 394180858640 in words is "three hundred ninety-four billion, one hundred eighty million, eight hundred fifty-eight thousand, six hundred forty".