398975809 has 8 divisors (see below), whose sum is σ = 408014208. Its totient is φ = 389960400.

The previous prime is 398975777. The next prime is 398975849. The reversal of 398975809 is 908579893.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 398975809 - 2⁵ = 398975777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (398975849) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32134 + ... + 42784.

It is an arithmetic number, because the mean of its divisors is an integer number (51001776).

Almost surely, 2^398975809 is an apocalyptic number.

It is an amenable number.

398975809 is a deficient number, since it is larger than the sum of its proper divisors (9038399).

398975809 is a wasteful number, since it uses less digits than its factorization.

398975809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11495.

The product of its (nonzero) digits is 4898880, while the sum is 58.

The square root of 398975809 is about 19974.3788138705. The cubic root of 398975809 is about 736.1769035864.

The spelling of 398975809 in words is "three hundred ninety-eight million, nine hundred seventy-five thousand, eight hundred nine".