81485688 has 64 divisors (see below), whose sum is σ = 217578240. Its totient is φ = 25369344.

The previous prime is 81485687. The next prime is 81485713. The reversal of 81485688 is 88658418.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81485681) by changing a digit.

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, 22020 + ... + 25452.

It is an arithmetic number, because the mean of its divisors is an integer number (3399660).

Almost surely, 2^81485688 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81485688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108789120).

81485688 is an abundant number, since it is smaller than the sum of its proper divisors (136092552).

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

81485688 is a wasteful number, since it uses less digits than its factorization.

81485688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3508 (or 3504 counting only the distinct ones).

The product of its digits is 491520, while the sum is 48.

The square root of 81485688 is about 9026.9423394636. The cubic root of 81485688 is about 433.5379425582.

The spelling of 81485688 in words is "eighty-one million, four hundred eighty-five thousand, six hundred eighty-eight".