867816809 has 2 divisors, whose sum is σ = 867816810. Its totient is φ = 867816808.

The previous prime is 867816791. The next prime is 867816853. The reversal of 867816809 is 908618768.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 733326400 + 134490409 = 27080^2 + 11597^2 .

It is a cyclic number.

It is not a de Polignac number, because 867816809 - 2¹⁶ = 867751273 is a prime.

It is not a weakly prime, because it can be changed into another prime (867816889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433908404 + 433908405.

It is an arithmetic number, because the mean of its divisors is an integer number (433908405).

Almost surely, 2^867816809 is an apocalyptic number.

It is an amenable number.

867816809 is a deficient number, since it is larger than the sum of its proper divisors (1).

867816809 is an equidigital number, since it uses as much as digits as its factorization.

867816809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1161216, while the sum is 53.

The square root of 867816809 is about 29458.7306074108. The cubic root of 867816809 is about 953.8410725357.

The spelling of 867816809 in words is "eight hundred sixty-seven million, eight hundred sixteen thousand, eight hundred nine".