394550081 has 4 divisors (see below), whose sum is σ = 394589892. Its totient is φ = 394510272.

The previous prime is 394550071. The next prime is 394550099. The reversal of 394550081 is 180055493.

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 can be written as a sum of positive squares in 2 ways, for example, as 201895681 + 192654400 = 14209^2 + 13880^2 .

It is a cyclic number.

It is not a de Polignac number, because 394550081 - 2¹⁸ = 394287937 is a prime.

It is a super-2 number, since 2×394550081² = 311339532834213122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (394550021) 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, 8021 + ... + 29213.

It is an arithmetic number, because the mean of its divisors is an integer number (98647473).

Almost surely, 2^394550081 is an apocalyptic number.

It is an amenable number.

394550081 is a deficient number, since it is larger than the sum of its proper divisors (39811).

394550081 is a wasteful number, since it uses less digits than its factorization.

394550081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39810.

The product of its (nonzero) digits is 21600, while the sum is 35.

The square root of 394550081 is about 19863.2847485002. The cubic root of 394550081 is about 733.4447073038. Note that the first 3 decimals are identical.

The spelling of 394550081 in words is "three hundred ninety-four million, five hundred fifty thousand, eighty-one".