85679609 has 4 divisors (see below), whose sum is σ = 90719604. Its totient is φ = 80639616.

The previous prime is 85679591. The next prime is 85679611. The reversal of 85679609 is 90697658.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 61669609 + 24010000 = 7853^2 + 4900^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85679609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (85679639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2519972 + ... + 2520005.

It is an arithmetic number, because the mean of its divisors is an integer number (22679901).

Almost surely, 2^85679609 is an apocalyptic number.

It is an amenable number.

85679609 is a deficient number, since it is larger than the sum of its proper divisors (5039995).

85679609 is a wasteful number, since it uses less digits than its factorization.

85679609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5039994.

The product of its (nonzero) digits is 816480, while the sum is 50.

The square root of 85679609 is about 9256.3280516628. The cubic root of 85679609 is about 440.8516717067.

The spelling of 85679609 in words is "eighty-five million, six hundred seventy-nine thousand, six hundred nine".