85247509 has 4 divisors (see below), whose sum is σ = 89734240. Its totient is φ = 80760780.

The previous prime is 85247473. The next prime is 85247531. The reversal of 85247509 is 90574258.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90574258 = 2 ⋅45287129.

It is a cyclic number.

It is not a de Polignac number, because 85247509 - 2²⁵ = 51693077 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85247549) 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, 2243337 + ... + 2243374.

It is an arithmetic number, because the mean of its divisors is an integer number (22433560).

Almost surely, 2^85247509 is an apocalyptic number.

It is an amenable number.

85247509 is a deficient number, since it is larger than the sum of its proper divisors (4486731).

85247509 is a wasteful number, since it uses less digits than its factorization.

85247509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4486730.

The product of its (nonzero) digits is 100800, while the sum is 40.

The square root of 85247509 is about 9232.9577601113. The cubic root of 85247509 is about 440.1093202883.

The spelling of 85247509 in words is "eighty-five million, two hundred forty-seven thousand, five hundred nine".