81836760 has 128 divisors (see below), whose sum is σ = 259200000. Its totient is φ = 20630016.

The previous prime is 81836731. The next prime is 81836773. The reversal of 81836760 is 6763818.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 411141 + ... + 411339.

It is an arithmetic number, because the mean of its divisors is an integer number (2025000).

Almost surely, 2^81836760 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 81836760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (129600000).

81836760 is an abundant number, since it is smaller than the sum of its proper divisors (177363240).

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

81836760 is a wasteful number, since it uses less digits than its factorization.

81836760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 385 (or 381 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 39.

The square root of 81836760 is about 9046.3672266828. The cubic root of 81836760 is about 434.1596671609.

The spelling of 81836760 in words is "eighty-one million, eight hundred thirty-six thousand, seven hundred sixty".