85579209 has 6 divisors (see below), whose sum is σ = 123614426. Its totient is φ = 57052800.

The previous prime is 85579181. The next prime is 85579213. The reversal of 85579209 is 90297558.

It is a happy number.

85579209 is a `hidden beast` number, since 8 + 557 + 92 + 0 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 59721984 + 25857225 = 7728^2 + 5085^2 .

It is not a de Polignac number, because 85579209 - 2¹⁵ = 85546441 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (85579229) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4754392 + ... + 4754409.

Almost surely, 2^85579209 is an apocalyptic number.

It is an amenable number.

85579209 is a deficient number, since it is larger than the sum of its proper divisors (38035217).

85579209 is a wasteful number, since it uses less digits than its factorization.

85579209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9508807 (or 9508804 counting only the distinct ones).

The product of its (nonzero) digits is 226800, while the sum is 45.

The square root of 85579209 is about 9250.9031450989. The cubic root of 85579209 is about 440.6794066514.

It can be divided in two parts, 8557 and 9209, that added together give a triangular number (17766 = T₁₈₈).

The spelling of 85579209 in words is "eighty-five million, five hundred seventy-nine thousand, two hundred nine".