398161 has 3 divisors (see below), whose sum is σ = 398793. Its totient is φ = 397530.

The previous prime is 398149. The next prime is 398171. The reversal of 398161 is 161893.

It is a happy number.

The square root of 398161 is 631.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 161893 = 97 ⋅1669.

It is not a de Polignac number, because 398161 - 2⁵ = 398129 is a prime.

It is a Duffinian number.

398161 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (398171) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 316 + ... + 946.

It is an arithmetic number, because the mean of its divisors is an integer number (132931).

398161 is a Friedman number, since it can be written as (3^6-98)^(1+1), using all its digits and the basic arithmetic operations.

2³⁹⁸¹⁶¹ is an apocalyptic number.

398161 is the 631-st square number.

398161 is the 316-th centered octagonal number.

It is an amenable number.

398161 is a deficient number, since it is larger than the sum of its proper divisors (632).

398161 is an frugal number, since it uses more digits than its factorization.

398161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1262 (or 631 counting only the distinct ones).

The product of its digits is 1296, while the sum is 28.

The cubic root of 398161 is about 73.5675409209.

Multiplying 398161 by its product of digits (1296), we get a square (516016656 = 22716²).

The spelling of 398161 in words is "three hundred ninety-eight thousand, one hundred sixty-one".