394340939 has 2 divisors, whose sum is σ = 394340940. Its totient is φ = 394340938.

The previous prime is 394340929. The next prime is 394340981. The reversal of 394340939 is 939043493.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (939043493) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 394340939 - 2⁴ = 394340923 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 394340939.

It is not a weakly prime, because it can be changed into another prime (394340929) 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 as a sum of consecutive naturals, namely, 197170469 + 197170470.

It is an arithmetic number, because the mean of its divisors is an integer number (197170470).

Almost surely, 2^394340939 is an apocalyptic number.

394340939 is a deficient number, since it is larger than the sum of its proper divisors (1).

394340939 is an equidigital number, since it uses as much as digits as its factorization.

394340939 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 314928, while the sum is 44.

The square root of 394340939 is about 19858.0195135366. The cubic root of 394340939 is about 733.3150902946.

The spelling of 394340939 in words is "three hundred ninety-four million, three hundred forty thousand, nine hundred thirty-nine".