398409 has 8 divisors (see below), whose sum is σ = 579552. Its totient is φ = 241440.

The previous prime is 398407. The next prime is 398417. The reversal of 398409 is 904893.

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

It is not a de Polignac number, because 398409 - 2¹ = 398407 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33), and also a Moran number because the ratio is a prime number: 12073 = 398409 / (3 + 9 + 8 + 4 + 0 + 9).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 398409.

It is not an unprimeable number, because it can be changed into a prime (398407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6004 + ... + 6069.

It is an arithmetic number, because the mean of its divisors is an integer number (72444).

2³⁹⁸⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

398409 is a deficient number, since it is larger than the sum of its proper divisors (181143).

398409 is a wasteful number, since it uses less digits than its factorization.

398409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12087.

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 398409 is about 631.1964828799. The cubic root of 398409 is about 73.5828119323.

It can be divided in two parts, 39 and 8409, that added together give a palindrome (8448).

The spelling of 398409 in words is "three hundred ninety-eight thousand, four hundred nine".