398781 has 12 divisors (see below), whose sum is σ = 586560. Its totient is φ = 261000.

The previous prime is 398771. The next prime is 398813. The reversal of 398781 is 187893.

It is not a de Polignac number, because 398781 - 2¹⁰ = 397757 is a prime.

It is a super-2 number, since 2×398781² = 318052571922, which contains 22 as substring.

398781 is a lucky 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 398781.

It is not an unprimeable number, because it can be changed into a prime (398711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 156 + ... + 906.

It is an arithmetic number, because the mean of its divisors is an integer number (48880).

2³⁹⁸⁷⁸¹ is an apocalyptic number.

It is an amenable number.

398781 is a deficient number, since it is larger than the sum of its proper divisors (187779).

398781 is a wasteful number, since it uses less digits than its factorization.

398781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 816 (or 813 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 398781 is about 631.4910925738. The cubic root of 398781 is about 73.6057065716.

The spelling of 398781 in words is "three hundred ninety-eight thousand, seven hundred eighty-one".