81934085 has 16 divisors (see below), whose sum is σ = 101862912. Its totient is φ = 63201600.

The previous prime is 81934079. The next prime is 81934087. The reversal of 81934085 is 58043918.

It is not a de Polignac number, because 81934085 - 2¹² = 81929989 is a prime.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81934087) 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, 50507 + ... + 52103.

It is an arithmetic number, because the mean of its divisors is an integer number (6366432).

Almost surely, 2^81934085 is an apocalyptic number.

It is an amenable number.

81934085 is a deficient number, since it is larger than the sum of its proper divisors (19928827).

81934085 is a wasteful number, since it uses less digits than its factorization.

81934085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1964.

The product of its (nonzero) digits is 34560, while the sum is 38.

The square root of 81934085 is about 9051.7448594180. The cubic root of 81934085 is about 434.3317082262.

The spelling of 81934085 in words is "eighty-one million, nine hundred thirty-four thousand, eighty-five".