85771581 has 16 divisors (see below), whose sum is σ = 130839168. Its totient is φ = 48960000.

The previous prime is 85771559. The next prime is 85771583. The reversal of 85771581 is 18517758.

It is not a de Polignac number, because 85771581 - 2¹⁵ = 85738813 is a prime.

It is a super-2 number, since 2×85771581² = 14713528214479122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85771583) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27081 + ... + 30081.

It is an arithmetic number, because the mean of its divisors is an integer number (8177448).

Almost surely, 2^85771581 is an apocalyptic number.

It is an amenable number.

85771581 is a deficient number, since it is larger than the sum of its proper divisors (45067587).

85771581 is a wasteful number, since it uses less digits than its factorization.

85771581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4372.

The product of its digits is 78400, while the sum is 42.

The square root of 85771581 is about 9261.2947798890. The cubic root of 85771581 is about 441.0093580421.

The spelling of 85771581 in words is "eighty-five million, seven hundred seventy-one thousand, five hundred eighty-one".