81689084 has 12 divisors (see below), whose sum is σ = 143041584. Its totient is φ = 40820064.

The previous prime is 81689071. The next prime is 81689087. The reversal of 81689084 is 48098618.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81689087) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2849 + ... + 13095.

It is an arithmetic number, because the mean of its divisors is an integer number (11920132).

Almost surely, 2^81689084 is an apocalyptic number.

It is an amenable number.

81689084 is a deficient number, since it is larger than the sum of its proper divisors (61352500).

81689084 is a wasteful number, since it uses less digits than its factorization.

81689084 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12244 (or 12242 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 44.

The square root of 81689084 is about 9038.2013697417. The cubic root of 81689084 is about 433.8983601098.

The spelling of 81689084 in words is "eighty-one million, six hundred eighty-nine thousand, eighty-four".