863869 has 2 divisors, whose sum is σ = 863870. Its totient is φ = 863868.

The previous prime is 863867. The next prime is 863879. The reversal of 863869 is 968368.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 544644 + 319225 = 738^2 + 565^2 .

It is a cyclic number.

It is not a de Polignac number, because 863869 - 2¹ = 863867 is a prime.

It is a super-2 number, since 2×863869² = 1492539298322, which contains 22 as substring.

Together with 863867, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (863867) 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 as a sum of consecutive naturals, namely, 431934 + 431935.

It is an arithmetic number, because the mean of its divisors is an integer number (431935).

2⁸⁶³⁸⁶⁹ is an apocalyptic number.

It is an amenable number.

863869 is a deficient number, since it is larger than the sum of its proper divisors (1).

863869 is an equidigital number, since it uses as much as digits as its factorization.

863869 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 62208, while the sum is 40.

The square root of 863869 is about 929.4455336382. The cubic root of 863869 is about 95.2392492281.

It can be divided in two parts, 863 and 869, that multiplied together give a palindrome (749947).

The spelling of 863869 in words is "eight hundred sixty-three thousand, eight hundred sixty-nine".