85365809 has 2 divisors, whose sum is σ = 85365810. Its totient is φ = 85365808.

The previous prime is 85365773. The next prime is 85365829. The reversal of 85365809 is 90856358.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64754209 + 20611600 = 8047^2 + 4540^2 .

It is a cyclic number.

It is not a de Polignac number, because 85365809 - 2¹⁶ = 85300273 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 85365809.

It is not a weakly prime, because it can be changed into another prime (85365829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42682904 + 42682905.

It is an arithmetic number, because the mean of its divisors is an integer number (42682905).

Almost surely, 2^85365809 is an apocalyptic number.

It is an amenable number.

85365809 is a deficient number, since it is larger than the sum of its proper divisors (1).

85365809 is an equidigital number, since it uses as much as digits as its factorization.

85365809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 259200, while the sum is 44.

The square root of 85365809 is about 9239.3619368439. The cubic root of 85365809 is about 440.3128095861.

The spelling of 85365809 in words is "eighty-five million, three hundred sixty-five thousand, eight hundred nine".