81680192 has 56 divisors (see below), whose sum is σ = 178186080. Its totient is φ = 36840960.

The previous prime is 81680191. The next prime is 81680231. The reversal of 81680192 is 29108618.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81680191) 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, 110159 + ... + 110897.

Almost surely, 2^81680192 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 81680192, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89093040).

81680192 is an abundant number, since it is smaller than the sum of its proper divisors (96505888).

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

81680192 is a wasteful number, since it uses less digits than its factorization.

81680192 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 919 (or 909 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 35.

The square root of 81680192 is about 9037.7094443227. The cubic root of 81680192 is about 433.8826160061.

The spelling of 81680192 in words is "eighty-one million, six hundred eighty thousand, one hundred ninety-two".