398401 has 4 divisors (see below), whose sum is σ = 405972. Its totient is φ = 390832.

The previous prime is 398393. The next prime is 398407. The reversal of 398401 is 104893.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 104893 = 29 ⋅3617.

It can be written as a sum of positive squares in 2 ways, for example, as 336400 + 62001 = 580^2 + 249^2 .

It is a cyclic number.

It is not a de Polignac number, because 398401 - 2³ = 398393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (398407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3706 + ... + 3811.

It is an arithmetic number, because the mean of its divisors is an integer number (101493).

2³⁹⁸⁴⁰¹ is an apocalyptic number.

It is an amenable number.

398401 is a deficient number, since it is larger than the sum of its proper divisors (7571).

398401 is an equidigital number, since it uses as much as digits as its factorization.

398401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7570.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 398401 is about 631.1901456772. The cubic root of 398401 is about 73.5823194180.

The spelling of 398401 in words is "three hundred ninety-eight thousand, four hundred one".