398784 has 56 divisors (see below), whose sum is σ = 1105408. Its totient is φ = 126720.

The previous prime is 398771. The next prime is 398813. The reversal of 398784 is 487893.

398784 = T₈₁ + T₈₂ + ... + T₁₄₂.

It is a house number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 398784.

It is an unprimeable number.

398784 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5919 + ... + 5985.

2³⁹⁸⁷⁸⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 398784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (552704).

398784 is an abundant number, since it is smaller than the sum of its proper divisors (706624).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

398784 is a wasteful number, since it uses less digits than its factorization.

398784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113 (or 103 counting only the distinct ones).

The product of its digits is 48384, while the sum is 39.

The square root of 398784 is about 631.4934678997. The cubic root of 398784 is about 73.6058911479.

The spelling of 398784 in words is "three hundred ninety-eight thousand, seven hundred eighty-four".