398320 has 40 divisors (see below), whose sum is σ = 999936. Its totient is φ = 146688.

The previous prime is 398311. The next prime is 398323. The reversal of 398320 is 23893.

398320 = 44² + 45² + ... + 108².

It is a happy number.

398320 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (40).

It is a hoax number, since the sum of its digits (25) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398323) 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, 849 + ... + 1231.

2³⁹⁸³²⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 398320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (499968).

398320 is an abundant number, since it is smaller than the sum of its proper divisors (601616).

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

398320 is a wasteful number, since it uses less digits than its factorization.

398320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 409 (or 403 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 398320 is about 631.1259779157. The cubic root of 398320 is about 73.5773323389.

The spelling of 398320 in words is "three hundred ninety-eight thousand, three hundred twenty".