394785209 has 24 divisors (see below), whose sum is σ = 496036800. Its totient is φ = 311429664.

The previous prime is 394785197. The next prime is 394785253. The reversal of 394785209 is 902587493.

It is a happy number.

It is not a de Polignac number, because 394785209 - 2¹² = 394781113 is a prime.

It is a super-2 number, since 2×394785209² = 311710722490347362, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (394785299) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 281492 + ... + 282890.

It is an arithmetic number, because the mean of its divisors is an integer number (20668200).

Almost surely, 2^394785209 is an apocalyptic number.

It is an amenable number.

394785209 is a deficient number, since it is larger than the sum of its proper divisors (101251591).

394785209 is a wasteful number, since it uses less digits than its factorization.

394785209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1869 (or 1862 counting only the distinct ones).

The product of its (nonzero) digits is 544320, while the sum is 47.

The square root of 394785209 is about 19869.2025255167. The cubic root of 394785209 is about 733.5903746091.

The spelling of 394785209 in words is "three hundred ninety-four million, seven hundred eighty-five thousand, two hundred nine".