398206809 has 48 divisors (see below), whose sum is σ = 772297344. Its totient is φ = 190944000.

The previous prime is 398206799. The next prime is 398206877. The reversal of 398206809 is 908602893.

It is not a de Polignac number, because 398206809 - 2⁵ = 398206777 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (398206409) 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 in 47 ways as a sum of consecutive naturals, for example, 13092 + ... + 31109.

It is an arithmetic number, because the mean of its divisors is an integer number (16089528).

Almost surely, 2^398206809 is an apocalyptic number.

398206809 is a gapful number since it is divisible by the number (39) formed by its first and last digit.

It is an amenable number.

398206809 is a deficient number, since it is larger than the sum of its proper divisors (374090535).

398206809 is a wasteful number, since it uses less digits than its factorization.

398206809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44238 (or 44235 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 398206809 is about 19955.1198693468. The cubic root of 398206809 is about 735.7036216347.

The spelling of 398206809 in words is "three hundred ninety-eight million, two hundred six thousand, eight hundred nine".