394243906 has 24 divisors (see below), whose sum is σ = 728384076. Its totient is φ = 159022080.

The previous prime is 394243903. The next prime is 394243919. The reversal of 394243906 is 609342493.

It can be written as a sum of positive squares in 2 ways, for example, as 340734681 + 53509225 = 18459^2 + 7315^2 .

It is not an unprimeable number, because it can be changed into a prime (394243903) 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 11 ways as a sum of consecutive naturals, for example, 116655 + ... + 119986.

Almost surely, 2^394243906 is an apocalyptic number.

394243906 is a deficient number, since it is larger than the sum of its proper divisors (334140170).

394243906 is a wasteful number, since it uses less digits than its factorization.

394243906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 236674 (or 236667 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 40.

The square root of 394243906 is about 19855.5761941073. The cubic root of 394243906 is about 733.2549379465.

The spelling of 394243906 in words is "three hundred ninety-four million, two hundred forty-three thousand, nine hundred six".