81041686 has 24 divisors (see below), whose sum is σ = 141485400. Its totient is φ = 34668480.

The previous prime is 81041671. The next prime is 81041711. The reversal of 81041686 is 68614018.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5736 + ... + 13963.

It is an arithmetic number, because the mean of its divisors is an integer number (5895225).

Almost surely, 2^81041686 is an apocalyptic number.

81041686 is a deficient number, since it is larger than the sum of its proper divisors (60443714).

81041686 is a wasteful number, since it uses less digits than its factorization.

81041686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19740 (or 19729 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 81041686 is about 9002.3155910021. The cubic root of 81041686 is about 432.7490825797.

The spelling of 81041686 in words is "eighty-one million, forty-one thousand, six hundred eighty-six".