81852066 has 64 divisors (see below), whose sum is σ = 189768960. Its totient is φ = 26127360.

The previous prime is 81852047. The next prime is 81852073. The reversal of 81852066 is 66025818.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 81852066.

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, 141570 + ... + 142146.

It is an arithmetic number, because the mean of its divisors is an integer number (2965140).

Almost surely, 2^81852066 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81852066, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94884480).

81852066 is an abundant number, since it is smaller than the sum of its proper divisors (107916894).

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

81852066 is a wasteful number, since it uses less digits than its factorization.

81852066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 696 (or 690 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 81852066 is about 9047.2131620737. The cubic root of 81852066 is about 434.1867325596.

The spelling of 81852066 in words is "eighty-one million, eight hundred fifty-two thousand, sixty-six".