393916849 has 2 divisors, whose sum is σ = 393916850. Its totient is φ = 393916848.

The previous prime is 393916847. The next prime is 393916891. The reversal of 393916849 is 948619393.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 228614400 + 165302449 = 15120^2 + 12857^2 .

It is a cyclic number.

It is not a de Polignac number, because 393916849 - 2¹ = 393916847 is a prime.

Together with 393916847, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 393916796 and 393916805.

It is not a weakly prime, because it can be changed into another prime (393916841) 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 as a sum of consecutive naturals, namely, 196958424 + 196958425.

It is an arithmetic number, because the mean of its divisors is an integer number (196958425).

Almost surely, 2^393916849 is an apocalyptic number.

It is an amenable number.

393916849 is a deficient number, since it is larger than the sum of its proper divisors (1).

393916849 is an equidigital number, since it uses as much as digits as its factorization.

393916849 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1259712, while the sum is 52.

The square root of 393916849 is about 19847.3385873270. The cubic root of 393916849 is about 733.0521172199.

The spelling of 393916849 in words is "three hundred ninety-three million, nine hundred sixteen thousand, eight hundred forty-nine".