398931 has 16 divisors (see below), whose sum is σ = 586656. Its totient is φ = 239616.

The previous prime is 398921. The next prime is 398933. The reversal of 398931 is 139893.

It is not a de Polignac number, because 398931 - 2¹⁰ = 397907 is a prime.

It is a super-2 number, since 2×398931² = 318291885522, which contains 22 as substring.

It is a nialpdrome in base 14.

It is a junction number, because it is equal to n+sod(n) for n = 398892 and 398901.

It is not an unprimeable number, because it can be changed into a prime (398933) 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, 1971 + ... + 2163.

It is an arithmetic number, because the mean of its divisors is an integer number (36666).

2³⁹⁸⁹³¹ is an apocalyptic number.

398931 is a deficient number, since it is larger than the sum of its proper divisors (187725).

398931 is a wasteful number, since it uses less digits than its factorization.

398931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 262.

The product of its digits is 5832, while the sum is 33.

The square root of 398931 is about 631.6098479283. The cubic root of 398931 is about 73.6149342529.

The spelling of 398931 in words is "three hundred ninety-eight thousand, nine hundred thirty-one".