398869 has 4 divisors (see below), whose sum is σ = 400140. Its totient is φ = 397600.

The previous prime is 398863. The next prime is 398887. The reversal of 398869 is 968893.

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.

It can be written as a sum of positive squares in 2 ways, for example, as 207025 + 191844 = 455^2 + 438^2 .

It is a cyclic number.

It is not a de Polignac number, because 398869 - 2⁹ = 398357 is a prime.

It is a super-2 number, since 2×398869² = 318192958322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398863) 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, 219 + ... + 919.

It is an arithmetic number, because the mean of its divisors is an integer number (100035).

2³⁹⁸⁸⁶⁹ is an apocalyptic number.

It is an amenable number.

398869 is a deficient number, since it is larger than the sum of its proper divisors (1271).

398869 is an equidigital number, since it uses as much as digits as its factorization.

398869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1270.

The product of its digits is 93312, while the sum is 43.

The square root of 398869 is about 631.5607650892. The cubic root of 398869 is about 73.6111204251.

The spelling of 398869 in words is "three hundred ninety-eight thousand, eight hundred sixty-nine".