394203689 has 4 divisors (see below), whose sum is σ = 430040400. Its totient is φ = 358366980.

The previous prime is 394203683. The next prime is 394203727. The reversal of 394203689 is 986302493.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 394203689 - 2⁴ = 394203673 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (394203683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17918339 + ... + 17918360.

It is an arithmetic number, because the mean of its divisors is an integer number (107510100).

Almost surely, 2^394203689 is an apocalyptic number.

It is an amenable number.

394203689 is a deficient number, since it is larger than the sum of its proper divisors (35836711).

394203689 is a wasteful number, since it uses less digits than its factorization.

394203689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35836710.

The product of its (nonzero) digits is 279936, while the sum is 44.

The square root of 394203689 is about 19854.5634301034. The cubic root of 394203689 is about 733.2300038755.

The spelling of 394203689 in words is "three hundred ninety-four million, two hundred three thousand, six hundred eighty-nine".