81831804 has 24 divisors (see below), whose sum is σ = 191394000. Its totient is φ = 27212544.

The previous prime is 81831787. The next prime is 81831809. The reversal of 81831804 is 40813818.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81831809) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2679 + ... + 13070.

It is an arithmetic number, because the mean of its divisors is an integer number (7974750).

Almost surely, 2^81831804 is an apocalyptic number.

It is an amenable number.

81831804 is an abundant number, since it is smaller than the sum of its proper divisors (109562196).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81831804 is a wasteful number, since it uses less digits than its factorization.

81831804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16189 (or 16187 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 33.

The square root of 81831804 is about 9046.0933004253. The cubic root of 81831804 is about 434.1509028079.

The spelling of 81831804 in words is "eighty-one million, eight hundred thirty-one thousand, eight hundred four".