863839 has 6 divisors (see below), whose sum is σ = 889224. Its totient is φ = 839160.

The previous prime is 863833. The next prime is 863843. The reversal of 863839 is 938368.

It is a happy number.

It is not a de Polignac number, because 863839 - 2⁷ = 863711 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a d-powerful number, because it can be written as 8 + 6⁷ + 8⁵ + 3 + 3⁹ + 9⁶ .

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 863798 and 863807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (863833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1054 + ... + 1684.

It is an arithmetic number, because the mean of its divisors is an integer number (148204).

2⁸⁶³⁸³⁹ is an apocalyptic number.

863839 is a deficient number, since it is larger than the sum of its proper divisors (25385).

863839 is an equidigital number, since it uses as much as digits as its factorization.

863839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 705 (or 668 counting only the distinct ones).

The product of its digits is 31104, while the sum is 37.

The square root of 863839 is about 929.4293948440. The cubic root of 863839 is about 95.2381467420.

Subtracting 863839 from its reverse (938368), we obtain a square (74529 = 273²).

The spelling of 863839 in words is "eight hundred sixty-three thousand, eight hundred thirty-nine".