85855781 has 16 divisors (see below), whose sum is σ = 95413248. Its totient is φ = 76604400.

The previous prime is 85855751. The next prime is 85855789. The reversal of 85855781 is 18755858.

It is a cyclic number.

It is not a de Polignac number, because 85855781 - 2⁶ = 85855717 is a prime.

It is a super-2 number, since 2×85855781² = 14742430262239922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85855789) 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, 247250 + ... + 247596.

It is an arithmetic number, because the mean of its divisors is an integer number (5963328).

Almost surely, 2^85855781 is an apocalyptic number.

It is an amenable number.

85855781 is a deficient number, since it is larger than the sum of its proper divisors (9557467).

85855781 is a wasteful number, since it uses less digits than its factorization.

85855781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 712.

The product of its digits is 448000, while the sum is 47.

The square root of 85855781 is about 9265.8394654775. The cubic root of 85855781 is about 441.1536204472.

The spelling of 85855781 in words is "eighty-five million, eight hundred fifty-five thousand, seven hundred eighty-one".