394540128 has 144 divisors (see below), whose sum is σ = 1175035680. Its totient is φ = 125411328.

The previous prime is 394540127. The next prime is 394540147. The reversal of 394540128 is 821045493.

394540128 is a `hidden beast` number, since 3 + 94 + 540 + 1 + 28 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 394540092 and 394540101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (394540127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 809901 + ... + 810387.

It is an arithmetic number, because the mean of its divisors is an integer number (8159970).

Almost surely, 2^394540128 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 394540128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (587517840).

394540128 is an abundant number, since it is smaller than the sum of its proper divisors (780495552).

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

394540128 is a wasteful number, since it uses less digits than its factorization.

394540128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 629 (or 618 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 394540128 is about 19863.0342093045. The cubic root of 394540128 is about 733.4385399106.

The spelling of 394540128 in words is "three hundred ninety-four million, five hundred forty thousand, one hundred twenty-eight".