81536916 has 24 divisors (see below), whose sum is σ = 194302080. Its totient is φ = 26600512.

The previous prime is 81536911. The next prime is 81536929. The reversal of 81536916 is 61963518.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81536911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71721 + ... + 72848.

It is an arithmetic number, because the mean of its divisors is an integer number (8095920).

Almost surely, 2^81536916 is an apocalyptic number.

It is an amenable number.

81536916 is an abundant number, since it is smaller than the sum of its proper divisors (112765164).

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

81536916 is a wasteful number, since it uses less digits than its factorization.

81536916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144623 (or 144621 counting only the distinct ones).

The product of its digits is 38880, while the sum is 39.

The square root of 81536916 is about 9029.7793992987. The cubic root of 81536916 is about 433.6287749884.

The spelling of 81536916 in words is "eighty-one million, five hundred thirty-six thousand, nine hundred sixteen".