85128993 has 6 divisors (see below), whose sum is σ = 122964114. Its totient is φ = 56752656.

The previous prime is 85128973. The next prime is 85129039. The reversal of 85128993 is 39982158.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 62916624 + 22212369 = 7932^2 + 4713^2 .

It is not a de Polignac number, because 85128993 - 2⁸ = 85128737 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (85128913) 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 5 ways as a sum of consecutive naturals, for example, 4729380 + ... + 4729397.

It is an arithmetic number, because the mean of its divisors is an integer number (20494019).

Almost surely, 2^85128993 is an apocalyptic number.

It is an amenable number.

85128993 is a deficient number, since it is larger than the sum of its proper divisors (37835121).

85128993 is a wasteful number, since it uses less digits than its factorization.

85128993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9458783 (or 9458780 counting only the distinct ones).

The product of its digits is 155520, while the sum is 45.

The square root of 85128993 is about 9226.5374328618. The cubic root of 85128993 is about 439.9052705847.

The spelling of 85128993 in words is "eighty-five million, one hundred twenty-eight thousand, nine hundred ninety-three".