398363909 has 2 divisors, whose sum is σ = 398363910. Its totient is φ = 398363908.

The previous prime is 398363893. The next prime is 398363921. The reversal of 398363909 is 909363893.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 392911684 + 5452225 = 19822^2 + 2335^2 .

It is an emirp because it is prime and its reverse (909363893) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 398363909 - 2⁴ = 398363893 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (398363939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199181954 + 199181955.

It is an arithmetic number, because the mean of its divisors is an integer number (199181955).

Almost surely, 2^398363909 is an apocalyptic number.

It is an amenable number.

398363909 is a deficient number, since it is larger than the sum of its proper divisors (1).

398363909 is an equidigital number, since it uses as much as digits as its factorization.

398363909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 944784, while the sum is 50.

The square root of 398363909 is about 19959.0558143415. The cubic root of 398363909 is about 735.8003585063.

The spelling of 398363909 in words is "three hundred ninety-eight million, three hundred sixty-three thousand, nine hundred nine".