398985 has 16 divisors (see below), whose sum is σ = 649536. Its totient is φ = 209088.

The previous prime is 398977. The next prime is 398989. The reversal of 398985 is 589893.

It is not a de Polignac number, because 398985 - 2³ = 398977 is a prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 398985.

It is not an unprimeable number, because it can be changed into a prime (398989) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 807 + ... + 1203.

It is an arithmetic number, because the mean of its divisors is an integer number (40596).

2³⁹⁸⁹⁸⁵ is an apocalyptic number.

It is an amenable number.

398985 is a deficient number, since it is larger than the sum of its proper divisors (250551).

398985 is a wasteful number, since it uses less digits than its factorization.

398985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 472.

The product of its digits is 77760, while the sum is 42.

The square root of 398985 is about 631.6525943903. The cubic root of 398985 is about 73.6182556519.

It can be divided in two parts, 39898 and 5, that added together give a triangular number (39903 = T₂₈₂).

The spelling of 398985 in words is "three hundred ninety-eight thousand, nine hundred eighty-five".