398404057 has 2 divisors, whose sum is σ = 398404058. Its totient is φ = 398404056.

The previous prime is 398404003. The next prime is 398404079. The reversal of 398404057 is 750404893.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 240374016 + 158030041 = 15504^2 + 12571^2 .

It is a cyclic number.

It is not a de Polignac number, because 398404057 - 2²³ = 390015449 is a prime.

It is not a weakly prime, because it can be changed into another prime (398408057) 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, 199202028 + 199202029.

It is an arithmetic number, because the mean of its divisors is an integer number (199202029).

Almost surely, 2^398404057 is an apocalyptic number.

It is an amenable number.

398404057 is a deficient number, since it is larger than the sum of its proper divisors (1).

398404057 is an equidigital number, since it uses as much as digits as its factorization.

398404057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120960, while the sum is 40.

The square root of 398404057 is about 19960.0615480013. The cubic root of 398404057 is about 735.8250762077.

The spelling of 398404057 in words is "three hundred ninety-eight million, four hundred four thousand, fifty-seven".