81830919540 has 48 divisors (see below), whose sum is σ = 230127166080. Its totient is φ = 21726284160.

The previous prime is 81830919539. The next prime is 81830919571. The reversal of 81830919540 is 4591903818.

It is a self number, because there is not a number n which added to its sum of digits gives 81830919540.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2964096 + ... + 2991575.

It is an arithmetic number, because the mean of its divisors is an integer number (4794315960).

Almost surely, 2^81830919540 is an apocalyptic number.

It is an amenable number.

81830919540 is an abundant number, since it is smaller than the sum of its proper divisors (148296246540).

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

81830919540 is a wasteful number, since it uses less digits than its factorization.

81830919540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5955912 (or 5955910 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 48.

The spelling of 81830919540 in words is "eighty-one billion, eight hundred thirty million, nine hundred nineteen thousand, five hundred forty".