863881 has 4 divisors (see below), whose sum is σ = 893700. Its totient is φ = 834064.

The previous prime is 863879. The next prime is 863887. The reversal of 863881 is 188368.

863881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 198025 + 665856 = 445^2 + 816^2 .

It is a cyclic number.

It is not a de Polignac number, because 863881 - 2¹ = 863879 is a prime.

It is a super-2 number, since 2×863881² = 1492580764322, which contains 22 as substring.

It is a Duffinian number.

863881 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (863887) 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, 14866 + ... + 14923.

It is an arithmetic number, because the mean of its divisors is an integer number (223425).

2⁸⁶³⁸⁸¹ is an apocalyptic number.

It is an amenable number.

863881 is a deficient number, since it is larger than the sum of its proper divisors (29819).

863881 is a wasteful number, since it uses less digits than its factorization.

863881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29818.

The product of its digits is 9216, while the sum is 34.

The square root of 863881 is about 929.4519890774. The cubic root of 863881 is about 95.2396902154.

The spelling of 863881 in words is "eight hundred sixty-three thousand, eight hundred eighty-one".