85372009 has 4 divisors (see below), whose sum is σ = 85418820. Its totient is φ = 85325200.

The previous prime is 85371989. The next prime is 85372013. The reversal of 85372009 is 90027358.

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 10497600 + 74874409 = 3240^2 + 8653^2 .

It is a cyclic number.

It is not a de Polignac number, because 85372009 - 2¹¹ = 85369961 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (85372099) 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 3 ways as a sum of consecutive naturals, for example, 20554 + ... + 24355.

It is an arithmetic number, because the mean of its divisors is an integer number (21354705).

Almost surely, 2^85372009 is an apocalyptic number.

It is an amenable number.

85372009 is a deficient number, since it is larger than the sum of its proper divisors (46811).

85372009 is a wasteful number, since it uses less digits than its factorization.

85372009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46810.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 85372009 is about 9239.6974517567. The cubic root of 85372009 is about 440.3234690971.

The spelling of 85372009 in words is "eighty-five million, three hundred seventy-two thousand, nine".