85109779 has 4 divisors (see below), whose sum is σ = 85233640. Its totient is φ = 84985920.

The previous prime is 85109753. The next prime is 85109789. The reversal of 85109779 is 97790158.

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

It is a cyclic number.

It is not a de Polignac number, because 85109779 - 2⁵ = 85109747 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (85109789) 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 in 3 ways as a sum of consecutive naturals, for example, 60894 + ... + 62275.

It is an arithmetic number, because the mean of its divisors is an integer number (21308410).

Almost surely, 2^85109779 is an apocalyptic number.

85109779 is a deficient number, since it is larger than the sum of its proper divisors (123861).

85109779 is a wasteful number, since it uses less digits than its factorization.

85109779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123860.

The product of its (nonzero) digits is 158760, while the sum is 46.

The square root of 85109779 is about 9225.4961384199. The cubic root of 85109779 is about 439.8721718892.

The spelling of 85109779 in words is "eighty-five million, one hundred nine thousand, seven hundred seventy-nine".