85405813 has 2 divisors, whose sum is σ = 85405814. Its totient is φ = 85405812.

The previous prime is 85405811. The next prime is 85405847. The reversal of 85405813 is 31850458.

It is an a-pointer prime, because the next prime (85405847) can be obtained adding 85405813 to its sum of digits (34).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47238129 + 38167684 = 6873^2 + 6178^2 .

It is a cyclic number.

It is not a de Polignac number, because 85405813 - 2¹ = 85405811 is a prime.

Together with 85405811, 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 (85405811) 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, 42702906 + 42702907.

It is an arithmetic number, because the mean of its divisors is an integer number (42702907).

Almost surely, 2^85405813 is an apocalyptic number.

It is an amenable number.

85405813 is a deficient number, since it is larger than the sum of its proper divisors (1).

85405813 is an equidigital number, since it uses as much as digits as its factorization.

85405813 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19200, while the sum is 34.

The square root of 85405813 is about 9241.5265513875. The cubic root of 85405813 is about 440.3815784258.

The spelling of 85405813 in words is "eighty-five million, four hundred five thousand, eight hundred thirteen".