394935840 has 432 divisors, whose sum is σ = 1562907528. Its totient is φ = 90243072.

The previous prime is 394935811. The next prime is 394935841. The reversal of 394935840 is 48539493.

It is a happy number.

It can be written as a sum of positive squares in 12 ways, for example, as 76527504 + 318408336 = 8748^2 + 17844^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (394935841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 5410044 + ... + 5410116.

Almost surely, 2^394935840 is an apocalyptic number.

394935840 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 394935840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (781453764).

394935840 is an abundant number, since it is smaller than the sum of its proper divisors (1167971688).

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

394935840 is a wasteful number, since it uses less digits than its factorization.

394935840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141 (or 113 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 45.

The square root of 394935840 is about 19872.9927288267. The cubic root of 394935840 is about 733.6836636501.

The spelling of 394935840 in words is "three hundred ninety-four million, nine hundred thirty-five thousand, eight hundred forty".