868686869 has 2 divisors, whose sum is σ = 868686870. Its totient is φ = 868686868.

The previous prime is 868686857. The next prime is 868686877. The reversal of 868686869 is 968686868.

868686869 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 619362769 + 249324100 = 24887^2 + 15790^2 .

It is a cyclic number.

It is not a de Polignac number, because 868686869 - 2⁸ = 868686613 is a prime.

It is a super-2 number, since 2×868686869² = 1509233752746046322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (868686899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 434343434 + 434343435.

It is an arithmetic number, because the mean of its divisors is an integer number (434343435).

Almost surely, 2^868686869 is an apocalyptic number.

It is an amenable number.

868686869 is a deficient number, since it is larger than the sum of its proper divisors (1).

868686869 is an equidigital number, since it uses as much as digits as its factorization.

868686869 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47775744, while the sum is 65.

The square root of 868686869 is about 29473.4943466159. The cubic root of 868686869 is about 954.1597349390.

Subtracting 868686869 from its reverse (968686868), we obtain a palindrome (99999999).

The spelling of 868686869 in words is "eight hundred sixty-eight million, six hundred eighty-six thousand, eight hundred sixty-nine".