394697689 has 3 divisors (see below), whose sum is σ = 394717557. Its totient is φ = 394677822.

The previous prime is 394697657. The next prime is 394697707. The reversal of 394697689 is 986796493.

The square root of 394697689 is 19867.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 394697689 - 2⁵ = 394697657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (394697609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 9934 + ... + 29800.

It is an arithmetic number, because the mean of its divisors is an integer number (131572519).

Almost surely, 2^394697689 is an apocalyptic number.

394697689 is the 19867-th square number.

394697689 is the 9934-th centered octagonal number.

It is an amenable number.

394697689 is a deficient number, since it is larger than the sum of its proper divisors (19868).

394697689 is an frugal number, since it uses more digits than its factorization.

394697689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39734 (or 19867 counting only the distinct ones).

The product of its digits is 17635968, while the sum is 61.

The cubic root of 394697689 is about 733.5361606777.

The spelling of 394697689 in words is "three hundred ninety-four million, six hundred ninety-seven thousand, six hundred eighty-nine".