867863809 has 2 divisors, whose sum is σ = 867863810. Its totient is φ = 867863808.

The previous prime is 867863783. The next prime is 867863813. The reversal of 867863809 is 908368768.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 779973184 + 87890625 = 27928^2 + 9375^2 .

It is a cyclic number.

It is not a de Polignac number, because 867863809 - 2⁷ = 867863681 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 867863809.

It is not a weakly prime, because it can be changed into another prime (867863869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433931904 + 433931905.

It is an arithmetic number, because the mean of its divisors is an integer number (433931905).

Almost surely, 2^867863809 is an apocalyptic number.

It is an amenable number.

867863809 is a deficient number, since it is larger than the sum of its proper divisors (1).

867863809 is an equidigital number, since it uses as much as digits as its factorization.

867863809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3483648, while the sum is 55.

The square root of 867863809 is about 29459.5283227685. The cubic root of 867863809 is about 953.8582918846.

The spelling of 867863809 in words is "eight hundred sixty-seven million, eight hundred sixty-three thousand, eight hundred nine".