394891969 has 4 divisors (see below), whose sum is σ = 395373780. Its totient is φ = 394410160.

The previous prime is 394891949. The next prime is 394891993. The reversal of 394891969 is 969198493.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 196420225 + 198471744 = 14015^2 + 14088^2 .

It is a cyclic number.

It is not a de Polignac number, because 394891969 - 2⁷ = 394891841 is a prime.

It is a super-2 number, since 2×394891969² = 311879334361393922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (394891949) 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 3 ways as a sum of consecutive naturals, for example, 239674 + ... + 241315.

It is an arithmetic number, because the mean of its divisors is an integer number (98843445).

Almost surely, 2^394891969 is an apocalyptic number.

It is an amenable number.

394891969 is a deficient number, since it is larger than the sum of its proper divisors (481811).

394891969 is an equidigital number, since it uses as much as digits as its factorization.

394891969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 481810.

The product of its digits is 3779136, while the sum is 58.

The square root of 394891969 is about 19871.8889137394. Note that the first 3 decimals coincide. The cubic root of 394891969 is about 733.6564958381.

The spelling of 394891969 in words is "three hundred ninety-four million, eight hundred ninety-one thousand, nine hundred sixty-nine".