398121 has 4 divisors (see below), whose sum is σ = 530832. Its totient is φ = 265412.

The previous prime is 398119. The next prime is 398129. The reversal of 398121 is 121893.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 398121 - 2¹ = 398119 is a prime.

It is an Ulam number.

It is a D-number.

It is a junction number, because it is equal to n+sod(n) for n = 398091 and 398100.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 398121.

It is not an unprimeable number, because it can be changed into a prime (398129) 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, 66351 + ... + 66356.

It is an arithmetic number, because the mean of its divisors is an integer number (132708).

2³⁹⁸¹²¹ is an apocalyptic number.

It is an amenable number.

398121 is a deficient number, since it is larger than the sum of its proper divisors (132711).

398121 is a wasteful number, since it uses less digits than its factorization.

398121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132710.

The product of its digits is 432, while the sum is 24.

The square root of 398121 is about 630.9683034828. The cubic root of 398121 is about 73.5650772608.

The spelling of 398121 in words is "three hundred ninety-eight thousand, one hundred twenty-one".