398561 has 4 divisors (see below), whose sum is σ = 408324. Its totient is φ = 388800.

The previous prime is 398557. The next prime is 398569. The reversal of 398561 is 165893.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14161 + 384400 = 119^2 + 620^2 .

It is a cyclic number.

It is not a de Polignac number, because 398561 - 2² = 398557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398569) 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, 4820 + ... + 4901.

It is an arithmetic number, because the mean of its divisors is an integer number (102081).

2³⁹⁸⁵⁶¹ is an apocalyptic number.

It is an amenable number.

398561 is a deficient number, since it is larger than the sum of its proper divisors (9763).

398561 is an equidigital number, since it uses as much as digits as its factorization.

398561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9762.

The product of its digits is 6480, while the sum is 32.

The square root of 398561 is about 631.3168776454. The cubic root of 398561 is about 73.5921684523.

It can be divided in two parts, 398 and 561, that added together give a palindrome (959).

The spelling of 398561 in words is "three hundred ninety-eight thousand, five hundred sixty-one".