85128247 has 4 divisors (see below), whose sum is σ = 85569520. Its totient is φ = 84686976.

The previous prime is 85128191. The next prime is 85128269. The reversal of 85128247 is 74282158.

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 85128247 - 2⁷ = 85128119 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 (85128287) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 220347 + ... + 220732.

It is an arithmetic number, because the mean of its divisors is an integer number (21392380).

Almost surely, 2^85128247 is an apocalyptic number.

85128247 is a deficient number, since it is larger than the sum of its proper divisors (441273).

85128247 is a wasteful number, since it uses less digits than its factorization.

85128247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441272.

The product of its digits is 35840, while the sum is 37.

The square root of 85128247 is about 9226.4970059064. The cubic root of 85128247 is about 439.9039855925.

The spelling of 85128247 in words is "eighty-five million, one hundred twenty-eight thousand, two hundred forty-seven".