85538581 has 2 divisors, whose sum is σ = 85538582. Its totient is φ = 85538580.

The previous prime is 85538573. The next prime is 85538647. The reversal of 85538581 is 18583558.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 81270225 + 4268356 = 9015^2 + 2066^2 .

It is a cyclic number.

It is not a de Polignac number, because 85538581 - 2³ = 85538573 is a prime.

It is a super-2 number, since 2×85538581² = 14633697678987122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85538281) 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 as a sum of consecutive naturals, namely, 42769290 + 42769291.

It is an arithmetic number, because the mean of its divisors is an integer number (42769291).

Almost surely, 2^85538581 is an apocalyptic number.

It is an amenable number.

85538581 is a deficient number, since it is larger than the sum of its proper divisors (1).

85538581 is an equidigital number, since it uses as much as digits as its factorization.

85538581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 192000, while the sum is 43.

The square root of 85538581 is about 9248.7069907096. The cubic root of 85538581 is about 440.6096593489.

The spelling of 85538581 in words is "eighty-five million, five hundred thirty-eight thousand, five hundred eighty-one".