398556 has 18 divisors (see below), whose sum is σ = 1007552. Its totient is φ = 132840.

The previous prime is 398549. The next prime is 398557. The reversal of 398556 is 655893.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 11071 = 398556 / (3 + 9 + 8 + 5 + 5 + 6).

It is a d-powerful number, because it can be written as 3¹⁰ + 9⁵ + 5 + 8³ + 5 + 6⁷ .

It is a nialpdrome in base 9.

It is a self number, because there is not a number n which added to its sum of digits gives 398556.

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 398556.

It is not an unprimeable number, because it can be changed into a prime (398557) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5500 + ... + 5571.

2³⁹⁸⁵⁵⁶ is an apocalyptic number.

398556 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

398556 is an abundant number, since it is smaller than the sum of its proper divisors (608996).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

398556 is a wasteful number, since it uses less digits than its factorization.

398556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11081 (or 11076 counting only the distinct ones).

The product of its digits is 32400, while the sum is 36.

The square root of 398556 is about 631.3129176565. The cubic root of 398556 is about 73.5918607099.

The spelling of 398556 in words is "three hundred ninety-eight thousand, five hundred fifty-six".