85372209 has 54 divisors (see below), whose sum is σ = 140584626. Its totient is φ = 49870080.

The previous prime is 85372193. The next prime is 85372211. The reversal of 85372209 is 90227358.

It is a happy number.

85372209 is a `hidden beast` number, since 85 + 372 + 209 = 666.

It can be written as a sum of positive squares in 9 ways, for example, as 28037025 + 57335184 = 5295^2 + 7572^2 .

It is not a de Polignac number, because 85372209 - 2⁴ = 85372193 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85372279) 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 in 53 ways as a sum of consecutive naturals, for example, 2082229 + ... + 2082269.

It is an arithmetic number, because the mean of its divisors is an integer number (2603419).

Almost surely, 2^85372209 is an apocalyptic number.

It is an amenable number.

85372209 is a deficient number, since it is larger than the sum of its proper divisors (55212417).

85372209 is a wasteful number, since it uses less digits than its factorization.

85372209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147 (or 94 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 85372209 is about 9239.7082746156. The cubic root of 85372209 is about 440.3238129437.

The spelling of 85372209 in words is "eighty-five million, three hundred seventy-two thousand, two hundred nine".