394075109 has 2 divisors, whose sum is σ = 394075110. Its totient is φ = 394075108.

The previous prime is 394075103. The next prime is 394075111. The reversal of 394075109 is 901570493.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 393030625 + 1044484 = 19825^2 + 1022^2 .

It is an emirp because it is prime and its reverse (901570493) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 394075109 - 2⁴ = 394075093 is a prime.

It is a Sophie Germain prime.

Together with 394075111, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (394075103) 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 as a sum of consecutive naturals, namely, 197037554 + 197037555.

It is an arithmetic number, because the mean of its divisors is an integer number (197037555).

Almost surely, 2^394075109 is an apocalyptic number.

It is an amenable number.

394075109 is a deficient number, since it is larger than the sum of its proper divisors (1).

394075109 is an equidigital number, since it uses as much as digits as its factorization.

394075109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34020, while the sum is 38.

The square root of 394075109 is about 19851.3251194977. The cubic root of 394075109 is about 733.1502743948.

The spelling of 394075109 in words is "three hundred ninety-four million, seventy-five thousand, one hundred nine".