398305 has 8 divisors (see below), whose sum is σ = 491112. Its totient is φ = 309888.

The previous prime is 398303. The next prime is 398311. The reversal of 398305 is 503893.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 33489 + 364816 = 183^2 + 604^2 .

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 398305 - 2¹ = 398303 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 9.

It is not an unprimeable number, because it can be changed into a prime (398303) 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, 892 + ... + 1261.

It is an arithmetic number, because the mean of its divisors is an integer number (61389).

2³⁹⁸³⁰⁵ is an apocalyptic number.

It is an amenable number.

398305 is a deficient number, since it is larger than the sum of its proper divisors (92807).

398305 is a wasteful number, since it uses less digits than its factorization.

398305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2195.

The product of its (nonzero) digits is 3240, while the sum is 28.

The square root of 398305 is about 631.1140942809. The cubic root of 398305 is about 73.5764087315.

It can be divided in two parts, 398 and 305, that added together give a triangular number (703 = T₃₇).

The spelling of 398305 in words is "three hundred ninety-eight thousand, three hundred five".