85171789 has 2 divisors, whose sum is σ = 85171790. Its totient is φ = 85171788.

The previous prime is 85171781. The next prime is 85171841. The reversal of 85171789 is 98717158.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 45670564 + 39501225 = 6758^2 + 6285^2 .

It is a cyclic number.

It is not a de Polignac number, because 85171789 - 2³ = 85171781 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85171781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42585894 + 42585895.

It is an arithmetic number, because the mean of its divisors is an integer number (42585895).

Almost surely, 2^85171789 is an apocalyptic number.

It is an amenable number.

85171789 is a deficient number, since it is larger than the sum of its proper divisors (1).

85171789 is an equidigital number, since it uses as much as digits as its factorization.

85171789 is an evil number, because the sum of its binary digits is even.

The product of its digits is 141120, while the sum is 46.

The square root of 85171789 is about 9228.8563213434. The cubic root of 85171789 is about 439.9789745463.

The spelling of 85171789 in words is "eighty-five million, one hundred seventy-one thousand, seven hundred eighty-nine".