394813649 has 4 divisors (see below), whose sum is σ = 395333220. Its totient is φ = 394294080.

The previous prime is 394813637. The next prime is 394813669. The reversal of 394813649 is 946318493.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 946318493 = 31 ⋅30526403.

It can be written as a sum of positive squares in 2 ways, for example, as 6723649 + 388090000 = 2593^2 + 19700^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-394813649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (394813669) 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, 258644 + ... + 260165.

It is an arithmetic number, because the mean of its divisors is an integer number (98833305).

Almost surely, 2^394813649 is an apocalyptic number.

It is an amenable number.

394813649 is a deficient number, since it is larger than the sum of its proper divisors (519571).

394813649 is an equidigital number, since it uses as much as digits as its factorization.

394813649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 519570.

The product of its digits is 559872, while the sum is 47.

The square root of 394813649 is about 19869.9181930878. The cubic root of 394813649 is about 733.6079899341.

The spelling of 394813649 in words is "three hundred ninety-four million, eight hundred thirteen thousand, six hundred forty-nine".