398307391 has 2 divisors, whose sum is σ = 398307392. Its totient is φ = 398307390.

The previous prime is 398307383. The next prime is 398307401. The reversal of 398307391 is 193703893.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 398307391 - 2³ = 398307383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (398307991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199153695 + 199153696.

It is an arithmetic number, because the mean of its divisors is an integer number (199153696).

Almost surely, 2^398307391 is an apocalyptic number.

398307391 is a deficient number, since it is larger than the sum of its proper divisors (1).

398307391 is an equidigital number, since it uses as much as digits as its factorization.

398307391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 122472, while the sum is 43.

The square root of 398307391 is about 19957.6399155812. The cubic root of 398307391 is about 735.7655595611.

The spelling of 398307391 in words is "three hundred ninety-eight million, three hundred seven thousand, three hundred ninety-one".